EP1268101B1 - Machine for bending and twisting flat metal wire - Google Patents

Abstract

A machine for bending and twisting flat metal wire for producing a motor vehicle wiper arm. The machine includes device for feeding and maintaining the wire, and at least a mechanism capable of gripping and releasing the wire in output of the feeding and maintaining device, and which is, under the action of a driver associated with a transmission device, mobile in several directions, rotating about the axis moving the wire, and moving, in one direction or another, in a direction perpendicular to the surfaces of the wire.

Description

The present invention relates to a machine for folding and the twisting of flat wire, particularly in view of the making a wiper arm for a motor vehicle (See, for example, US-A-4,367,641).

The arm of a wiper is made by folding a wire flat metal, for example substantially rectangular or similar, to allow it to resist the constraints to which it is subject, and to ensure the perfect maintenance of the wiper blade which, so, can not turn on said wire. This wire is bent for a allow him to marry, at a distance, the contours of the vehicle, and on the other hand give it the best orientation adapted, so that during its alternative movement, the broom be perfectly applied against the glass.

However, because of the substantially rectangular section of the wire, it can only be bent in two opposite directions which correspond to the two big sides, also to bend the wire in other directions it is necessary to associate the folding twisting of the thread.

The realization of the pleat (s) and the tendrils disadvantages because it is difficult to achieve a spin on a wire already folded and vice versa, so that said folds and tendrils are not executed in a rigorous way which may cause adjustment problems when mounting wiper arm.

The present invention aims to remedy this drawback by proposing a machine allowing to realize continuously folds and tendrils, alternately and possibly in simultaneous.

The machine for folding and twisting flat wire into particular view of the realization of a wiper arm for motor vehicle object of the present invention is characterizes essentially in that it comprises means feeding and maintenance of the yarn, and at least one means adapted to gripping and releasing said yarn at the output of said means and maintenance, and that is, under the action of means associated with transmission means, mobile in several directions, on the one hand in rotation around the axis of movement of said wire, and secondly on the move, in a direction or in another, in a direction perpendicular to faces of said wire.

The different movements that can accomplish the means suitable for seize the output wire of the feeding and holding means, allow to make folds and tendrils on a wire.

Thus, the rotation about an axis of movement of the wire in allows twisting, while moving, in one direction or in another, perpendicular to the faces of said wire allows perform the folding.

According to an additional feature of the machine according to the invention, the means capable of grasping and releasing the wire in output of said feeding and holding means is suitable for coming practically in contact with the extreme part of the means for feeding and maintaining said wire.

According to another additional feature of the machine according to the invention, the means capable of grasping and releasing the wire at the outlet of the feeding and holding means, is movable in rotation about a radial axis to the axis of movement of said wire and parallel to the faces of it.

Such a displacement in rotation of the means capable of grasping and release the wire at the outlet of the feeding and holding means said wire makes it possible to perform the folding movement of the wire.

According to another additional feature of the machine according to the invention, the means capable of grasping and releasing the wire at the output of the means for feeding and maintaining the wire, consists in a moving means in axial displacement along a radial axis at the axis of movement of said wire and parallel to the faces thereof.

The axial displacement of the means capable of grasping and releasing the wire output means for feeding and maintaining said wire allows disengaging said means after a folding operation and / or twisting.

According to a particular embodiment of the folding machine and twisting according to the invention, the means capable of grasping and release the wire out of the means of feeding and maintenance present in the form of a stirrup intended to come, by a axial movement, straddling said wire, said caliper comprising two parallel branches separated by a space of a width corresponding to the thickness of said wire.

According to a preferred embodiment of the machine of folding and twisting according to the invention, it comprises a body annular shape positioned around the means of development and maintaining said wire, able to rotate axially about the axis of moving the wire, and on the edge of which is mounted a tool holder adapted to cause a tool to rotate about an axis radial to said axis of movement of the wire and parallel to the faces of the latter, and able to allow the disengagement of said tool said thread.

The advantages and characteristics of the machine according to invention, will become clearer from the description which follows and which refers to the annexed drawing, which represents a non-limiting embodiment.

In the appended drawing, the single figure represents a view schematic partial and in perspective of a machine for the bending and twisting of flat wire in particular to the manufacture of a wiper arm for a motor vehicle according to the invention.

With reference to this figure, we can see the bending head 1 of a machine according to the invention, for folding and twisting of a wire 2 of rectangular section which thus presents two faces 20.

The yarn 2 is held by a feeding and holding means 3, able to drive axially along an axis X and to immobilize the wire 2.

The bending head 1 comprises a body 4 in the form of a ring in the opening 40 which passes the end portion 30 of the means of feeding and maintenance 3, of which only a part is visible. The body 4 is mobile in rotation according to the double arrow V, around of the X axis, under the action of motor means associated with transmission means, not shown.

The body 4 carries an element 5 in which a tool holder can rotate 50 along a Y axis radial to the X axis and parallel to the faces 20 of the wire 2, and which preferably passes not far from the end, not visible, means for feeding and maintaining 3 of the wire 2, the rotation of the tool holder 50 being represented by an arrow double P.

The tool holder 50 carries, eccentrically relative to the Y axis, a tool 51 in the form of stirrup which thus comprises two branches 52 separated by a space of slightly width greater than the wire thickness 2. In addition, the tool 51 is moving in axial displacement, parallel to the Y axis, this displacement being represented by a double arrow S.

It will be noted that the axial movement of the tool 51 can be realized either by its displacement in the tool holder 50, or by the displacement of the latter in element 5, either by movement of the element 5 on the body 4.

It will also be noted that when the axial movement of the tool 51 is achieved by its displacement in the tool holder 50, it is possible that the latter contains several tools presenting different characteristics, dimensional for example, each likely to be extracted according to the nature of the folding to achieve.

It should also be noted that in a variant not represented, the twisting movement according to V is carried out by the displacement of the element 5 on the body 4 by a system with rack and pinion for example.

The realization of a fold on the wire 2 is carried out in the manner following, the wire 2 is moved along X of the desired length, then it is maintained by the means of feeding and maintaining 3 while the tool 51 is approaching the wire 2 and that its two branches 52 ride this one near the party end of the feeding means 3. The rotation P of the tool, the makes the axial rotation along Y of the tool holder 50, allows then to bend the wire 2.

Note that the radius of rotation of the tool 51 according to Y is preferably small, too, the extreme part 30 has clearances 31 allowing the passage of the tool 51.

The wire 2 being folded and held in the tool 51, it is not possible to move it along X, or to turn the tool 51, also the latter is moved axially along S then brought back into its initial position, thus allowing the release of the wire 2.

To perform a spin on the wire 2, we proceed in a first time in the same way, that is after the displacement along X of the wire 2, the blocking of the latter in the means of feeding and maintenance, and setting up the tool to horse on the wire 2, we realize a spin by the rotation according to V of the body 4, the continuation of the folding being again subordinate the axial disengagement of the tool 51.

The machine according to the invention also comprises means, not shown, cutting the wire 2, allowing a manufacturing in continued.

The machine according to the invention makes it possible to enchain folds and the twists, these movements being of course made by through stepper motors digitally controlled.

Claims (6)

1. Machine for bending and twisting flat metal wire, namely for making a windscreen-wiper arm for a motor vehicle, characterised in that it includes means (3) for arranging and maintaining the wire (2), and at least means (51) capable of seizing and releasing said wire (2) when exiting said means (3) for arranging and maintaining, and which is, under the action of driving means associated with transmission means, movable in several directions, on the one hand in rotation (V) about the axis (X) of displacement of said wire (2), and, on the other hand, in displacement, in one direction or another, in a direction (P) perpendicular to the faces (50) of said wire (2).
2. Machine according to claim 1, characterised in that the means (51) capable of seizing and releasing the wire (2) when exiting the means (3) for arranging and maintaining is capable of entering almost into contact with the outermost portion (30) of said means for arranging and maintaining the wire (2).
3. Machine according to claim 1 or claim 2, characterised in that the means (51) capable of seizing and releasing the wire (2) when exiting the means (3) for arranging and maintaining the wire (2) is movable in rotation (P) about an axis (Y) radial to the axis (X) of displacement of said wire (2) and parallel to the faces (20) of the latter.
4. Machine according to any of the preceding claims, characterised in that the means capable of seizing and releasing the wire (2) when exiting the means (3) for arranging and maintaining the wire (2) consists of means (51) movable in axial displacement (S) along an axis (X) of displacement of said wire (2) and parallel to the faces (20) of the latter.
5. Machine according to any of the preceding claims, characterised in that the means capable of seizing and releasing the wire (2) when exiting the means (3) for arranging and maintaining are in the form of a strap (51) aimed, through an axial movement, at straddling said wire (2), said strap (51) including two parallel legs (52) separated by a space having a width corresponding to the thickness of said wire (2).
6. Machine according to any of the preceding claims, characterised in that it includes a body (4) having an annular shape and positioned around the means (3) for arranging and maintaining the wire (2), capable of rotating axially about the axis (X) of displacement of said wire (2), and on the edge of which is fitted a tool bolder (50) capable of driving a tool (51) in rotation (P) about an axis (Y) radial to said axis (X) of displacement of the wire (2) and parallel to the faces (20) of the latter, and capable of allowing releasing (S) said tool (51) from said wire (2).

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