Bending machine and process

Abstract

The invention relates to a bending machine (M) for bending a workpiece (300), remarkable in that a clamping jaw (511) is supported by a clamping jaw holder (510) receiving at least two clamping jaws (511, 512) arranged back to back, the clamping jaw holder (510) being fastened to a shelf (513) guided and driven in translation on the bending arm (500), the support shelves (600) punctually receiving the clamping jaw holder (510) separated from the shelf (513) and to move it on either side of the bending axis transversely to the advance axis of the workpiece (300) to be bent, independently of the bending arm (500) so that the clamping jaw holder (510) can be fastened again to the shelf (513) once the bending arm (500) has been rotated 180 degrees. The invention also relates to a bending process.

Claims

1. A bending machine (M) for bending a workpiece (300), comprising: a frame (100); and a bending head (400), the workpiece (300) to be bent being movable in a controlled manner at least axially relative to the frame (100), said bending head (400) moving transversely to an advance axis of the workpiece (300) to be bent and supporting at least one bending roller (410, 420) provided with a bending jaw, the roller (410, 420) defining a bending axis not parallel to the advance axis of the workpiece (300) to be bent, a bending arm (500) being associated with said roller (410, 420) and rotating in a controlled manner about the bending axis, at least one clamping jaw (511, 512) supported by the bending arm (500) and arranged opposite the bending jaw with which the at least one clamping jaw is to cooperate for the purpose of driving a portion of workpiece (300) to be bent in a clamped manner between said clamping jaw (511, 512) and said bending jaw, said clamping jaw (511, 512) being movable in a controlled manner on the arm (500) in order to clamp or unclamp said portion of the workpiece (300) to be bent, a ruler holder (600) configured to slide parallel to an advance axis of the workpiece (300) to be bent and supporting at least two straight rulers (601, 602) arranged back-to-back, the workpiece (300) to be bent being in contact with a first ruler of said rulers during the bending thereof, the ruler holder being driven and guided in translation on the bending head (400) transversely to the advance axis of the workpiece (300) to be bent, wherein: said clamping jaw (511) is supported by a clamping jaw holder (510) accommodating at least two clamping jaws (511, 512) arranged back-to-back, the clamping jaw holder (510) is reversibly fastened to a shelf (513), which is guided and driven in translation on the bending arm (500), and the ruler holder (600) and the clamping jaw holder (510) are provided with fastening means configured such that the ruler holder (600) accommodates the clamping jaw holder (510) separated from the shelf (513) and enables movement of the clamping jaw holder (510) on either side of the bending axis in a starting position transverse to the advance axis of the workpiece (300) to be bent and independently of the bending arm (500) so that the clamping jaw holder (510) can be fastened to the shelf (513) once the bending arm (500) is rotated 180 degrees.

2. The bending machine (M) according to claim 1, wherein said fastening means is formed of a first of male and female shapes provided on the ruler holder (600), configured to cooperate with a corresponding second of said male and female shapes preformed in the clamping jaw holder (510) for reception and displacement of the clamping jaw holder (510) on either side of the bending axis.

3. The bending machine (M) according to claim 2, wherein said ruler holder comprises: a part movable in translation for sliding parallel to an advance axis of the workpiece (300) to be bent, said movable part supporting said rulers; and a fixed part that is fixed in translation parallel to the advance axis of the workpiece (300) to be bent, on which said movable part slides, said fixed part being provided with the first of said male or female shapes.

4. The bending machine (M) according to claim 1, wherein said clamping jaw holder (510) is provided with a first of male and female shapes cooperating with a corresponding second of said male and female shapes provided on said shelf (513).

5. The bending machine (M) according to claim 1, wherein said clamping jaw holder (510) is provided with male cylindrical projections preformed with flats for cooperating with buttonhole-shaped holes formed of a large-diameter hole with a smaller and oblong hole for retaining the clamping jaw holder or releasing the clamping jaw holder, depending on a position of the cylindrical projections in said buttonhole-shaped holes.

6. The bending machine (M) according to claim 1, wherein the bending head (400) accommodates a first pair of horizontally arranged rails for guiding the ruler holder (600), and a second pair of vertically arranged rails for guiding an assembly formed by the roller (410, 420) and the bending arm (500).

7. The bending machine (M) according to claim 1, wherein the workpiece (300) to be bent is brought to the bending head by means of a guided carriage (200) and driven in translation on the frame (100) parallel to an axis of the workpiece (300) to be bent.

8. The bending machine (M) according to claim 1, wherein the bending arm (500) associated with the bending roller (410, 420) is driven and guided in translation on the bending head (400) transversely to an advance axis of the workpiece (300) to be bent and parallel to the transverse movement of the ruler holder (600).

9. The bending machine (M) according to claim 1, wherein the bending head (400) has a parallelepiped body (430) comprising a vertical rear face (431), a horizontal upper face (432), and a vertical front face (433), the vertical rear face (431) cooperating with the frame (100) for horizontal and vertical guidance and drive of the bending head (400), the horizontal upper face (432) cooperating with the ruler holder (600) for horizontal and transverse guidance and drive of the ruler holder (600), and the vertical front face (433) cooperating with the assembly formed by the roller (410, 420) and the bending arm (500) for horizontal and vertical guidance and drive of the parallelepiped body.

10. A bending process executed by the bending machine (M) according to claim 1, wherein the process comprises: fastening the clamping jaw holder (510) provided on the bending arm (500) to the ruler holder (600); moving the clamping jaw holder (510) from the bending arm (500); rotating the bending arm (500); moving the ruler holder (600) with the clamping jaw holder (510) fastened thereto; fastening the clamping jaw holder (510) on the bending arm (500) upon reaching a new starting position; and moving the clamping jaw holder (510) from the ruler holder (600).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIGS. 1 to 9 are schematic drawings of perspective views of a same bending head of an embodiment of a bending machine according to the invention executing a plurality of operations related to bending.

(2) FIG. 10 is a drawing of a detail perspective view of the clamping jaw holder associated with the ruler holder and separated from the shelf;

(3) FIG. 11 is a drawing of a detail perspective view of the clamping jaw holder fastened to the shelf.

DESCRIPTION OF AN EMBODIMENT

(4) As illustrated in FIG. 1, the bending machine denoted M as a whole comprises a fixed frame 100 on the upper surface 110 of which slides along the double arrow F1 a mobile carriage 200 provided with a carriage hollow shaft 210 in which the workpiece 300 to be bent is arranged (here a tube).

(5) This hollow shaft 210 allows through an internal clamping mandrel the said tube 300 to be guided and immobilized in rotation and in translation. It also defines the advance axis of the tube.

(6) Frame 100 has a vertical front face 120, relative to which a bending head 400 moves. This bending head 400 includes: two bending rollers 410 and 420 defining a vertical bending axis Y and each intended for bending in a different direction, a bending arm 500 that pivots around the vertical axis Y for the bending of the tube 300 according to the double arrow F2. The bending arm 500 is shown here positioned for bending in the trigonometric direction. It is cinematically associated with the rollers.

(7) The bending arm 500 is provided with a clamping jaw holder 510 that moves horizontally in translation according to the double arrow F3. It moves towards the bending roller 410, which is preformed with a jaw to clamp a portion of tube 300 between the arm and the roller.

(8) This clamping jaw holder 510 is provided with two clamping jaws arranged back to back: a first clamping jaw 511 is intended to cooperate with a jaw 410′ of the roller 410 for bending in the trigonometric direction, a second clamping jaw 512 arranged symmetrically, i.e., back to back with respect to the first clamping jaw, and intended to cooperate with a jaw 420′ of the roller 420 for clockwise bending.

(9) The bending head 400 also comprises a ruler holder 600 with at least two straight members 601 and 602, hereinafter called “rulers”, arranged back-to-back: a first ruler 601 for the tight support of the tube when bending counterclockwise, and a second ruler 602 for the tight support of the tube when bending clockwise.

(10) To achieve this tight support, the ruler holder 600 is movable in translation according to double-arrow F4.

(11) According to the invention, the bending head 400 is designed to achieve a plurality of additional movements.

(12) To do this, it has a substantially parallelepiped 430 body, of which: the vertical rear face 431 cooperates with the vertical front face 120 defined by the frame 100 for horizontal and vertical guidance and drive of the entire bending head 400; the horizontal top face 432 cooperates with the ruler holder 600 for horizontal guidance and drive of the latter allowing it not only to bring a ruler in contact with the tube but also to make the ruler holder 600 move on each side of the axis of the tube so as to use any of the rulers 601 or 602 it supports; the vertical front face 433 cooperates with the assembly formed by the bending rollers 410, 420 and the arm 500 for horizontal and vertical guidance and drive of this assembly.

(13) As illustrated, the execution of a motion in translation on an axis is carried out by pairs of rails 431, 437 possibly associated with a cross-shelf for an associated perpendicular motion in translation.

(14) As shown, the bending head 400 of the invention is very compact.

(15) In the phase of the bending range illustrated by the drawing in FIG. 1, the bending arm, the tube 300 and the rollers are arranged so that counterclockwise bending can take place. A portion of the tube 300 is clamped between the roller 410 and the clamping jaw 511. The ruler 601 is in contact with the tube 300.

(16) From this position, as shown in FIG. 2, the bending arm 500 starts a counterclockwise rotation according to the arrow F5 about the Y axis of the rollers. The ruler holder 600 moves together with the tube 300 with a translation parallel to the axis of the tube 300 according to the arrow F6.

(17) Once the bending has been completed, as illustrated in FIG. 3, the clamping jaw holder 510 moves away from the roller 410 and the bending arm 500 returns to the starting position. The clamping jaw holder 510 is positioned relative to the ruler holder 600 so that the clamping jaw holder 510 is punctually fastened to the ruler holder 600 and is separated from the shelf 513 of the arm 500 as illustrated in FIG. 4. To this end, the clamping jaw holder 510 is fixed in a removable manner to a shelf 513 guided and driven in translation on the bending arm 500 and the ruler holder 600 comprises means for gripping and/or accommodating the clamping jaw holder 510.

(18) Several solutions for fastening the clamping jaw holder 510 to the shelf 513 have been considered. For example, in a non-limiting manner, this fastening can be achieved by clamping the clamping jaw holder on the shelf through buttonhole-type means moved pneumatically. An example is illustrated by FIGS. 10 and 11.

(19) Referring to these figures, said clamping jaw holder 510 is provided with male shapes cooperating with corresponding female shapes fitted to said shelf 513. More precisely, said clamping jaw holder 510 is provided with male cylindrical projections 514 preformed with flats 515 cooperating with buttonhole-shaped holes 516 associating a large diameter hole with a smaller and oblong hole in order to retain or release the clamping jaw holder according to the position of its projections in said buttonhole holes.

(20) Several solutions for fastening the clamping jaw holder 510 with respect to the ruler holder 600 have also been considered.

(21) According to one embodiment, said punctual fastening means comprise male or female shapes 517 fitted to the ruler support 600 and cooperating with corresponding female or male shapes 519 preformed in the clamping jaw holder 510 for reception and displacement purposes of the clamping jaw holder 510 on either side of the bending axis.

(22) The ruler holder 600 includes: a part movable in translation for sliding parallel to the advance axis of the workpiece 300 to be bent, said movable part supporting said rulers, a fixed part being fixed in translation parallel to the advance axis of the workpiece 300 to be bent on which the said movable part slides, said fixed part being provided with said male or female shapes.

(23) For example, in a non-limiting manner, this fastening can be achieved by 2 axes which pneumatically come out of the said fixed part and which hold the clamping jaw holder 510 in position during the lateral movement of the ruler holder 600. Another solution is a magnetic solution.

(24) Another solution for fastening/detachment uses “Belleville” cones and washers.

(25) The bending head 400 is first lowered with respect to tube 300 to allow the movements of the next phase in preparation for the next bending operation to be performed in a clockwise direction.

(26) As shown in FIG. 5, the clamping jaw holder 600 with the clamping jaw holder 510 punctually fastened thereto is moved in translation according to arrow F7 to the other side of the advance axis of tube 300 in order to position the ruler 602 in the working position and also to move the clamping jaw holder 510 in its initial orientation without reversing its position in order to use the clamping jaw 512.

(27) The arm and roller assembly is moved in translation according to arrow F8 and arrow F9 to move to the other side of the advance axis of the tube 300.

(28) As shown in FIG. 6, the arm 500 is positioned by rotating according to the arrow F10, in the starting position for a clockwise bending. The shelf 513 then moves into position along the arm 500 so as to be placed below the clamping jaw holder 510 carried by the ruler holder 600.

(29) As shown in FIG. 7, the arm and roller assembly moves up in translation according to arrow F11 to allow the fastening of the clamping jaw holder 510 to the shelf 513 and the separation between the clamping jaw holder 510 and the ruler holder 600. This movement also makes it possible to put at the right height the roller 420 which will be used for bending clockwise.

(30) From this position, as shown in FIG. 8, the clamping jaw holder 510 is moved in translation according to the arrow F12 along the arm 500 to tighten the portion of the tube 300 to be bent between the roller 420 and the clamping jaw 512. In the same way, the ruler holder 600 is moved in translation according to the arrow F13 on the bending head 400 for the shelf 602 to come in contact with the tube 300 and to tightly support this tube for bending.

(31) FIG. 9 shows the clockwise bending according to arrow F14.

(32) FIG. 9 clearly illustrates the increased angular possibilities of the bending machine of the invention which, by the increased movement capacities of its respective subassemblies can position the arm and roller assembly at the end of the transverse translation stroke. This positional position ensures that there is no obstacle to the rotation of the arm 500 according to the arrow F14 going beyond 180 degrees.

(33) Of course, various arrangements, modifications and improvements can be made to the above examples, without departing from the scope of the invention.