MXPA06000992A - Bending device for bending machine - Google Patents

Abstract

A bending device for bending machine comprises a matrix (2), a countermatrix (6), and a die (7) able to prevent wrinkles.A countermatrix-holder support element (8) is fixed on an upper slide (10), which is slidable transversally to a workpiece T to be bent on a lower slide (11) movable in turn in the same direction of the upper slide (10), on a table (12). A first double-acting cylinder (19), being fixed on said lower slide (11), moves the countermatrix (6) toward and away from the workpiece (T);and a second double-acting cylinder (24) is slidable on the upper slide (10) and connected to a slider (25) on a counteracting rod (26) which is pivoted about an end of an arm-turning spindle (3), so that a force is exerted on the countermatrix-holder support element (8) in a projecting portion (23) thereof.

Description

- - POPULATION DEVICE FOR DOUBLE MACHINE FIELD OF THE INVENTION The present invention relates to a bending device for a bending machine. Even if in the following description a fixed radius tube bending machine is taken as an example of a bending machine, it is clear that the invention is not considered limited to said machine but that the invention can also be constituted to a variable radius tube bending machine. . Furthermore, the invention can also be used for working not only on tubes but also on bar sections in general, which are referred to in the following as workpieces.

BACKGROUND OF THE INVENTION Such a bending device comprises a rotary bending die or die and a vise facing the die. Said vise is mounted on a bending arm and holds a section of the workpiece immediately after the section to be bent, according to a feed direction of the workpiece. The bending device also comprises a pressure die or counter die, which is located directly before the clamped section of the workpiece. work, the contramatriz does not turn together with the arm of bent. When the workpiece is stretched around the die, the countermatrix moves along with the workpiece, to resist the radial opposing forces of the workpiece. In addition to the countermatrix, a die capable of preventing undulations is mounted on the non-rotating part of the bending machine opposite the countermatrix and is adjustable in its position with respect to the matrix configuration. The non-rotating part of the bending machine, which can be of any known kind, for example, is shaped as either a cabinet or as a longitudinal member, with or without a mandrel, and is not relevant to the present invention and is not it will be described here. Some problems that arise in the known benders are first of all related to the construction of the countermatrix unit which must be very robust and therefore bulky to withstand the opposite forces exerted by a workpiece that is worked. In fact, the construction deficiency of the countermatrix unit generates work defects, such as a radius that is not uniform of a bend and not correct dimensions of the workpiece. For this reason, such construction needs a special design which contributes to increase the costs of the bending machines.

- In addition, in known bending machines, the die capable of preventing undulations is driven by its own drive control to be correctly positioned with respect to the work piece. Such a drive control of the die is able to avoid corrugations and is located opposite to the drive control which is used to place the countermatrix. This requires that an operator presents certain problems when moving around the machine to place both the die able to avoid the undulations as the countermatrix, according to the piece to be folded.

BRIEF DESCRIPTION OF THE INVENTION The present invention attempts to correct the drawbacks mentioned above. An object of the invention is to provide countermatrix constructions and arrangements so that they are less robust and bulky, and therefore cheaper in comparison with those normally used in known benders, but at the same time have an equal efficiency to resist opposite forces. of the piece that is worked. Another object of the invention is to provide a simple and reliable means of operation of the countermatrix. In addition, an object of the invention is - providing a die operating means capable of preventing undulations of the body from being controlled from one side of the machine. According to the invention, a bending device for bending machine comprises a bending die or die, a pressure die or counter die and a die capable of preventing undulations. Matrix, matrix around which the work piece is folded, is mounted on an arm spinning spindle. The countermatrix, which is adapted to withstand opposing forces of the workpiece in a bending operation, is held by the counter-bracket support member which is fixed to an upper slider "which is slidably mounted in a transverse direction the work piece on a lower slide which in turn can be moved in the same direction as the upper slide on a table.The die is able to avoid undulations and is held by its die support element so that this oriented towards the countermatrix The countermatrix exerts on the workpiece an adequate pressure by a first operating means comprising a first and second double action cylinders.The first double acting cylinder is fixed on the lower slide and has a first rod of cylinder piston acting on a portion of the element of - backing-bra support to move the countermatrix towards and away from the work piece. The second double-acting cylinder is slidable on the upper slide and is connected to a slide on a counter-acting rod that is pivoted about an end of an arm turning spindle. The slide is designed to come up against a first stop on the counter-action rod, so that a second cylinder piston rod exerts a force on the counter-support support member in a projection portion thereof which is located beyond the portion where the first cylinder piston rod operates. Advantageously, the second double-acting cylinder is slidably mounted additionally through a vertical plate on a threaded rod that is rigidly connected to the support case, the vertical plate is designed to bump against a second stop on the threaded rod when the slide on the opposite action rod hits the first stop. It should be noted that the previous modification with two stops makes the first operating medium more resistant than that with a "single stop." In addition, the countermatrix and the die capable of avoiding undulations exert on the workpiece one - adequate pressure by a second operating means acting on the die able to avoid undulations through the support elements of the countermatrix and the die able to avoid undulations before a bending arm, which is fixed around the turning spindle of arm, performs a bending operation by holding and stretching a section of the work piece. The second operating means comprises a die slide on which the die support element is mounted for a die capable of preventing undulations, the die slide is slidably mounted on the table, through a connecting means. , to the 'lower slide.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be described with reference to its preferred embodiments, in relation to the accompanying drawings, in which: Figure 1 shows, in a perspective view, a first embodiment of a folding device, in accordance with the invention,; figure 2 shows in a top plan view, the first embodiment of the doubler device in figure 1, with a work piece that is to be folded which is placed on the device but which is not clamped between the countermatrix and the die able to avoid undulations; Figure 3 shows, in a top plan view, the first embodiment of the bending device in figure 1, with a work piece that is to be folded that is placed on the device and that is held in countermatrix and the die capable of avoid undulations; Figure 4 shows in a perspective view a second embodiment of a bending device according to the invention with a work piece that is to be folded and that is placed on the device but that is not clamped between the countermatrix and the capable die to avoid undulations; and figure 5. shows a view in left exploded elevation ... of .. the second embodiment of the doubler device of the figure. DETAILED DESCRIPTION OF THE PREFERRED MODALITIES With reference to the drawings, in FIG. 1, in a perspective view, a first embodiment of the bending device according to the invention is shown, as it is mounted in a support cabinet 1 of a bending machine The bending machine extends in the left direction in the figure, and is not shown. A bending die or die 2 is pivotally mounted on the support cabinet 1 around a pivot spindle 3. As is usual in this class of machines, a bending arm 4 is fixed around the arm rotation spindle 3 in order to oscillate with the latter. The bending arm 4 is provided with a vise 5 designed to hold a piece to be bent, that is, a tube T, as shown in figures 2 and 3 which are seen on the upper floor of the same bending machine. The tube T is held by the vise 5 in its section immediately after the section to be bent, according to a feeding direction of the tube T, which is indicated by an arrow F in figures 2 and 3 In addition, the tube T is subjected to a pressure between the pressure die or counter matrix 6 and a die 7 able to prevent undulations, in a section before the die 2, according to the arrow F. The counter matrix 6 remains slidable in its support element 8 in the feeding direction of the tube T by means of a prismatic articulation whose shroud is indicated by the number 9 in figure 1. The counter-bracket support element 8 is capable of resisting opposing forces of the T tube during the bending operation. The countermatrix 6 can be moved in a known manner along the support element 8. With reference to FIG. 2 in particular, according to a first embodiment of the invention, the counter-bracket support element 8 is fixed on an upper slide 10. The upper slide 10 is slidable transversely with respect to the tube T on a lower slide 11, which in turn can be moved in the same direction of the upper slide 10 on the table 12. The table 12 is fixed transversely to the cabinet 1 of support, projecting therefrom with a front table portion 13 and a rear table portion 14. Opposite to the countermatrix 6 on the same table 12 is the die 7 capable of preventing undulations, which is maintained by its die support element 15 slidably mounted by a prismatic articulation 29 on a slide 16 that slides transversely on the table 12 in the same direction of the slide 11. According to the first embodiment of the present invention, the slide 16 is connected to the slide 11 through the connecting means, such as a separator 17 whose width depends on the diameter of the tube T that is going to bend. In the portion 13 of the front table there is provided a driving device that moves the slides 11 and 16 rapidly back and forth, which are connected together by a separator 17, the driving device is, for example, an arrow 18 with a screw and nut assembly (not shown) which is located between the slider 11 and the table 12 and which is operated by a manual wheel (not shown).

By virtue of the distribution described in the foregoing, when operating both the arrow 18 and the prismatic articulation 29, the die 7 is able to prevent undulations from being placed with respect to the matrix 2, and also the counter matrix 6, mounted on its element 8 of support opposite the die 7, which can be approximated to the die 2 according to a selection of the separator 17. The separator 17 has various sizes based on a work piece and the kind of worked. In addition, a first double-acting cylinder 19, having a piston rod 22, operates on the counter-bracket support element 8, which is fixed on the upper slide 10. The stroke of the piston rod is established by a manually controlled knob 20 of the first double action cylinder 19 in order to obtain a micrometric adjustment of the position of the countermatrix 6 before and after the working operation. The first double acting cylinder 19 is fixed on the lower slide 11 by means of clamps 21, 21, so that the upper slide 10 can move in the same direction as the first cylinder piston rod 22 with respect to the table 12. Therefore, the assembly of the slides 10, 11 and 16 can move quickly forward and towards - back by means of arrow 18 with a screw and nut assembly. The first double action cylinder 19 is part of a first operating means which acts directly on the support 8 of the counter-brace element. The first cylinder piston rod 22 acts on a portion of the support element 8 to move the countermatrix 6 towards the tube T to be bent and vice versa, away from it. On a projection portion 23, which is cantilevered with respect to the table 12 of the support element 8, a second double action cylinder 24 operates as another part of the first operation means. The second cylinder 24 of double action, which. it has a piston rod 27, slidably mounted on the slide 10 by means of a sliding guide 25 which can be moved on a rod 26 of opposite action. The counter-acting rod 26 is pivoted about one end of the arm rotation spindle 3. The second cylinder piston rod 27 (shown in Figures 2 and 3) abuts the projection portion 23 of the support member 8. On the counter action rod 26 there is a first adjustable stop 28. This first adjustable stop 28 is represented diagramatically as a pair of nuts which are screwed into a threaded portion of the counter-acting rod 26 and can be immobilized as - studs. When the second cylinder piston rod 27 extends out of the cylinder 24, the slide guide 25 is designed to come up against the first adjustable stop 28 on the counter-acting rod 26 such that the second cylinder piston rod 27 it applies a force on the counter-bracket support member 8 in its projecting portion 23, which is located beyond the portion where the first cylinder piston rod 22 operates. When both of the first operating means in the form of two double-acting cylinders 19, 24 are controlled through a pressurized fluid, such as oil fed by one or more hydraulic circuits (which are not shown in details), the die pressure or the countermatrix and the die capable of preventing undulations exert on the tube to be bent a suitable pressure that counteracts the opposing forces exerted by the tube T in the bending operation thereof. A second operating means acting on the die capable of preventing undulations is represented by the slide 16 (figure 1) on which the support element 15 of the die 7 capable of preventing undulations is mounted. The slide 16 which, as mentioned in the above, is connected to a first slide 11 by means of a separator 17, it is placed by the arrow 18 with a screw and nut assembly. With reference to Figure 2, the countermatrix 6 retained by its support element 8 is still shown away from the tube T, while the die 7 is able to prevent undulations is located in advance near the tube T. The correct distance is determined by the separator 17 connecting the slides 11 and 16, and by the micrometric adjustment of the knob 20 of the first double action cylinder 19. With reference to Figure 3, the upper slide 10 is observed moved with respect to the lower slide 11 by the operation of the first double-action cylinder 19 and the second double-action cylinder 24. The first double action cylinder 19, which is fixed to the lower slide 11, acts directly on the first rod 22 of cylinder piston on the support element 8. The second double-acting cylinder 24 can be moved on the counter-acting rod 26 by the slide guide 25. As the slide guide 25 abuts on the first stop 28 properly adjusted, the second cylinder piston rod 27 presses the portion 23 of projection against the tube T. In this way, the countermatrix 6, mounted slidably on the support element 8 can - apply an adequate pressure without structural deformations on the tube which counteracts while being bent. Referring now to Figures 4 and 5, a second embodiment of a bending device according to the present invention is shown. In Figures 4 and 5, which are a perspective view and a left elevation view, respectively, of the folding device partially in cross section, like reference numbers are used to indicate parts equal or similar to those of the first embodiment . With reference to Figure 4 in particular, according to the second embodiment of 1 invention, the counter-support support-holder element 8 is fixed on a slide 10. The slide 10 is slidable transversely with respect to the tube T on the table 12 The table 12 is transversely fixed to a support cabinet 1, which is projecting therefrom with a front table portion 13 and a rear table portion 14. Mounted opposite the countermatrix 6 of the same table 12 is a die 7 capable of preventing undulations, which is retained by its die support member 15 slidably mounted on a slide 16 which slides transversely on the table 12 in the same direction of the slide 10. In a different manner to the first embodiment, the slide 16 is adjustable in its position on the table 12 independently of the slide 10. In the front table portion 13 there is provided a driving device that moves the slide 10 rapidly towards forward and backward by a flexible transmission 30 and "a coupling of pulleys 31, 32. The pulley 3-1 is meshed with the arrow of a motor 33, and the pulley 32 engages an arrow 18 with a screw assembly- screw nut (not shown) - which is located between the slide 10 and the table 12. It should be noted that the anterior distribution, in which the arrow 18 with the screw and nut assembly is part of the The operation that acts directly only on the counter-bracket support element 8, should not be considered preferable with respect to the first embodiment of the invention. In this second embodiment, only for purposes of clarity, the first double action cylinder of the first operation means is not shown, since it would cover other characteristics that will be described in the following. On a projection portion 23 of the support element 8, in addition to the portion on which the arrow 18 acts with a screw and nut assembly and which is cantilevered on the slide 10, an additional part of the element operating means 8 counter-bracket support bra in the form of a double action 24 cylinder operates. The hydraulic supply circuits of the double-acting cylinder 24 are not shown. The double action cylinder 24 is slidably mounted by means of a sliding guide 25 on a counter-rotating rod 26. The counter-acting rod 26 is rotated about one end of the arm rotation spindle 3. The piston rod 27 of the cylinder 24 (shown in FIG. 5) abuts on the projection portion 23 of the support element 8 on the counter-acting rod 26 there is a first adjustable stop 28. The first adjustable stop 28 is shown. diagramatically as a pair of nuts which are screwed into a threaded portion of the counter-acting rod 26 and can be immobilized as bolts -prisoners. The sliding guide 25 and the integral cylinder 24 thereto are rigidly connected to a vertically distributed plate and extending downwardly. The plate 34 has in the lower part a through hole for a threaded rod 35. A second stop 36, preferably in the form of a sleeve having - - a hexagonal head portion 37 and a smooth portion 38 is threaded internally as the threaded rod 35. The second stop 36 can be adjusted in its position along the threaded rod 35 by means of a nut tightening wrench which engages the hexagonal head portion 37 of the second stop 36. The plate 34 is slidable on the portion 38 of the second stop 36 and the mutual position between the plate 34 and the second stop 36 is fixed through a nut 39 when it is pressed against the hexagonal head portion 37. The threaded rod 35 is connected, for example, by a threaded coupling, to a block 40 of the cabinet 1, as shown in FIG. 5. In the work, by using the operating means of the counter-bracket support element-holder according to the second In the embodiment of the bending device, the sliding guide 25 is designed to abut against the stop 28 on the counter-acting rod 26 and the vertical plate 34 is designed to come up against the second stop 36 correspondingly adjusted in its position on the threaded rod 35. In this way, when the slide 10 holding the support element 8 is moved by the operation unit 30-33 so that the countermatrix 6 is placed - - against the tube T, the double acting cylinder 24 is also operated in such a way that its piston rod 27 exerts a force on the same counter-bracket support element 8 in its projecting portion 23. The entire construction of the bending device suitably resists this force of the double action cylinder 24, since the latter is counteracted in the upper part by the sliding guide 25 which makes contact against the first stop 28 on the rod 26 of opposite action , which is pivoted around the spindle 3 of arm rotation, and in the lower part through the vertical plate 34, by the second stop 36 on the threaded rod 35, which is screwed to the block 40 integral to the cabinet 1. Such an opposite action distribution, according to the second embodiment, allows the bending device of the present invention to work with tubes having a diameter as well as a thickness greater than those which can be worked in a bending machine without such distribution of opposite action . It should be appreciated that this reduces the costs of a bending operation. The invention has been described by way of examples only in two embodiments thereof, but changes and modifications can be made without departing from the scope of the appended claims.

Claims (9)

1. Bending device for bending machine, comprising: a die or bender die, mounted on 5 an arm turning spindle around which a workpiece is bent, a pressure die or counter-die, which is held by its support element. ~ counter-brace and is adapted -.- "to resist opposing forces of the workpiece in a bending operation 0, a die capable of preventing undulations, which is retained by a die support element of ; • _, .. way that faces the contrama.triz,: both the - _. counter-matrix as the die are able to prevent • - produce undulations on the work piece by exerting an adequate pressure by a first operation means acting on the countermatrix and a second operation means acting on the punch able to avoid undulations through the support elements of the countermatrix and the die capable of preventing undulations before the bending arm, which is fixed around the arm turning spindle, performing a bending operation by holding and pulling a section of the workpiece, characterized in that: the backstop support element - the fastener is fixed on an upper slide which is slidably mounted in a direction transverse to the work piece on a lower slide which in turn can be moved in the same direction as the upper slide on the table; the first operating means comprises: a first double-acting cylinder which is fixed on the lower slide and which has a first cylinder piston rod acting on a portion of the counter-bracket support element to move the countermatrix toward and away from it of the work piece; and a second double-acting cylinder which is slidable on the upper slide and is connected to a slide guide on a counter-acting rod that is pivoted about one end of the arm turning spindle, the slide guide is designed for bumping against a first stop on the opposite-action rod so that a second cylinder piston rod exerts a force on the counter-support holder-fastener in a projecting portion thereof in which it is located beyond the portion where the first cylinder piston rod acts; and the second operating means comprises a slide on which a die support element is mounted for a die capable of preventing undulations, the slide is slidable on the table, integrally, through the connection means, towards the lower slide.

2. Bender device as described in claim 1, characterized in that the connection means - between the die support element for a die capable of preventing undulations and the lower slider comprises a separator having various sizes based on the work piece and the kind of worked.

3. Bender device as described in claim 1, characterized in that the first double acting cylinder is provided with an adjustment knob - .. manual by means of which the first cylinder piston rod is adjusted in its stroke.

4. Bender device as described in the claim. 1, characterized in that the projection portion of the support element of -. counter-bracket on which the second cylinder piston rod presses is cantilevered with respect to 15 the table.

5. Bender device as described in claim 1, characterized in that the first stop is adjustable in its position on the rod of opposite action.

6. Bender device as described in claim 5, characterized in that the first adjustable stop is formed with a pair of nuts similar to studs on a threaded section of the counter-acting rod. 25

7. Bender device as described in - claim 1, characterized in that the second double-acting cylinder, which is slidable through the slide on the counter-acting rod, is pivoted about one end of the arm turning spindle, and is slidably mounted further through of a vertical plate on the threaded rod rigidly connected to the support cabinet, the vertical plate is designed to come up against a second stop on the threaded rod when the sliding guide on the opposite action rod comes up against the first stop.

8. Bender device as described in claim 7, characterized in that the second stop is adjustable on the threaded rod.

9. Bender device as described in claim 8, characterized in that the second stop is in the form of an internally threaded sleeve having a hexagonal head portion and a smooth portion, which externally couples the vertical plate, the second stop is adjustable in its position along the threaded rod by actuation on the hexagonal head portion by means of a wrench for tightening nuts.