EP2339055B1 - Circular needling machine whereby a fibrous web is supplied by means of a conveyor and a vertical chute - Google Patents

Abstract

The machine for circularly needling a textile structure formed from a helical fibrous layer (106), comprises a needling table placed under a table (100) for supplying a fibrous sheet to the needle. The supply needle comprises a circular conveyor (102) centered on a vertical axis, and is disposed in the fibrous layer. The conveyor has a radial slot sealed in it for continuously rolling the fibrous web disposed on the conveyor. The slot is sealed in the conveyor towards a straight duct that extends vertically between the conveyor and a tray centered on the vertical axis (104) of the conveyor. The machine for circularly needling a textile structure formed from a helical fibrous layer (106), comprises a needling table placed under a table (100) for supplying a fibrous sheet to the needle. The supply needle comprises a circular conveyor (102) centered on a vertical axis, and is disposed in the fibrous layer. The conveyor has a radial slot sealed in it for continuously rolling the fibrous web disposed on the conveyor. The slot is sealed in the conveyor towards a straight duct that extends vertically between the conveyor and a tray centered on the vertical axis (104) of the conveyor, where the support plate includes a unit for rotating the fibrous web around the vertical axis. The needling table comprises a guiding plate centered on vertical axis and movable vertically according to the support plate between a low position of operation in which it is based on the support plate and a raised position to release in which it is positioned above the support plate. The straight duct has a secured portion to the feed table and another secured portion to the plate for guiding the needling table, where the portions are adapted to translate one inside the other during the vertical movements of the guide plate. The unit for rotating the fibrous web includes two pairs of tapered rollers angularly spaced from each other, and is intended to come into contact with the fibrous web feed on the needling table. The conical roller is connected to the guiding plate of the needling table, and disposed on outlet of the straight duct. The supply roller further comprises a roller disposed in the conveyor and angularly intercalated between the slot and inlet of the duct. A unit is arranged for evacuation of the textile structure apart from the support plate of the needling table, and comprises an arm controller equipped with an articulated rod. The needling table comprises a unit for cutting fibrous layer. The circular conveyor of the supply table comprises two curved portions each present in the form of semi-disc and disposed side by side. The slot is formed by a space connected between two portions of the conveyor.

Description

Background of the invention

The present invention relates to the general field of circular needling machines for producing needled textile structures, and more particularly relates to the automatic supply of fibrous webs of such machines.

It is known to use a circular type needling machine for the manufacture of annular textile structures intended to constitute the fibrous reinforcement of annular pieces made of composite material, in particular brake discs, such as discs made of carbon / carbon composite material. (C / C) for airplane brakes.

In such a needling machine, a fibrous helical fibrous web is placed on a needling table and driven in rotation by drive means most often friction. The feed of this type of machine can be made flat at the needling table from a sheet of stuffing material delivered from a peeling device external to the needling machine.

Document is also known WO 02/088449 a needling machine in which the supply of fibrous sheets needling is performed automatically. For this purpose, the needling machine comprises a storage basket disposed above the needling table and containing the fibrous sheet to needling, a set of conical rollers for continuously extracting the sheet from the storage basket and a chute. helical to take the unrolled web of the storage basket and bring it to the needling table at friction drive means. This needling machine, however, has the disadvantage that the conical rollers driving the fibrous web cause a sliding of the fibrous web during its unwinding, which results in a deformation of the fibrous web when it arrives on the web. needling table.

Object and summary of the invention

The main object of the present invention is thus to overcome such disadvantages by proposing a circular needling machine for which the supply of the needling table in fibrous webs takes place automatically and without deformation thereof.

This object is achieved by means of a circular needling machine of a textile structure formed from a helical fibrous web, comprising a needling table disposed under a helical fiber fibrous web supplying table, and in which according to the invention, the feed table comprises a circular conveyor centered on a vertical axis and on which is intended to be arranged a helical fibrous sheet needle, the conveyor having a radial slot opening under the circular conveyor to unroll in continuous fibrous web disposed on the conveyor, the slot opening under the conveyor to a substantially straight chute which extends vertically between the conveyor and a support plate of the needling table centered on the vertical axis of the conveyor so as to resume the unrolled web of the conveyor and bring it to the needling table, said support plate having means for rotation of the fibrous web around the vertical axis.

The presence of a circular conveyor makes it possible to deliver the fibrous web without tension, which tension is then guided vertically towards the needling table by means of the chute. Thus, no deformation of the fibrous web appears before needling. In addition, compared to a helical chute, the presence of a substantially straight chute saves space to position other functions of the machine (as the engagement of the fibrous web and its automatic cutting).

According to an advantageous arrangement, the needling table further comprises a guide plate centered on the vertical axis and movable vertically with respect to the support plate between a low operating position in which it rests on said support plate and a raised position of clearance in which it is positioned above said support plate.

In this case, the chute has a portion secured to the feed table and another portion secured to the guide plate of the needling table, these portions being able to translate one inside the other during vertical movements of the guide plate.

The means for rotating the fibrous web may comprise two pairs of conical rollers angularly spaced apart from one another and intended to come into contact with the fibrous web brought onto the needling table.

The machine may further comprise a conical pressure roller secured to the plate of the needling table and disposed at the outlet of the chute.

The feed table may further comprise a roller disposed under the circular conveyor and angularly interposed between the inlet of the slot and the chute so as to allow the recovery of a free end of the unrolled sheet of the conveyor and its guiding towards the chute.

Means for evacuating the textile structure from the support plate of the needling table may be provided, these means advantageously comprising a manipulator arm provided with an articulated finger for gripping and evacuating the textile structure. Cutting means of the fibrous web may also be provided.

Preferably, the circular conveyor of the feed table comprises two curved conveyor portions each in the form of a half-disc and which are disposed face to face, the slot being formed by a space left between the two conveyor portions.

Brief description of the drawings

• la figure 1 est une vue générale en perspective d'une machine d'aiguilletage circulaire selon l'invention;
• la figure 2 montre de façon schématique en vue de dessus et en écorché la table d'alimentation de la machine d'aiguilletage de la figure 1;
• la figure 3 est une vue en coupe selon III-III de la figure 2 ;
• la figure 4 est une vue schématique et de dessus de la table d'aiguilletage de la machine d'aiguilletage de la figure 1 ;
• les figures 5A et 5B sont des vues schématiques montrant la table d'aiguilletage de la machine d'aiguilletage de la figure 1 dans deux positions différentes ; et
• la figure 6 montre de façon schématique la table d'évacuation de la machine d'aiguilletage de la figure 1.

Other features and advantages of the present invention will emerge from the description given below, with reference to the accompanying drawings which illustrate an embodiment having no limiting character. In the figures:

• the figure 1 is a general perspective view of a circular needling machine according to the invention;
• the figure 2 shows schematically in top view and cutaway the feed table of the needling machine of the figure 1 ;
• the figure 3 is a sectional view along III-III of the figure 2 ;
• the figure 4 is a schematic view from above of the needling table of the needling machine of the figure 1 ;
• the Figures 5A and 5B are schematic views showing the needling table of the needling machine of the figure 1 in two different positions; and
• the figure 6 shows schematically the discharge table of the needling machine of the figure 1 .

Detailed description of an embodiment

The figure 1 schematically illustrates a circular needling machine 10 according to the invention. This machine is intended for the needling of a textile structure, or annular preform formed from a fibrous web (or band) helical.

The needling machine 10 comprises a table 100 for supplying a fibrous sheet with needling, a needling table 200 placed under the feed table, and a table 300 for removing the needle-punched structure from the table. needling.

The needling fibrous web supply table 100 comprises a circular conveyor 102 which is centered on a vertical axis 104 and on which is disposed a fibrous fibrous web 106. The fibrous web is more precisely wound in several layers around a central shaft 108 centered on the vertical axis 104 and is rotated around this axis by the circular conveyor.

As shown on Figures 1 to 3 the circular conveyor 102 of the feed table is more precisely composed of two curved conveyor portions 102a, 102b each in the form of a half-disc and which are arranged opposite one another (the straight edges of these conveyor portions are parallel and face to face). The direction of rotation of these curved conveyor portions is directed so as to cause a complete turn of 360 ° to the fibrous web 106 about the vertical axis 104.

Each conveying curved portion 102a, 102b therefore makes it possible to perform a 180 ° half-turn to the fibrous web 106. For this purpose, in a manner known per se, each curved conveyor portion comprises an endless band 110a, 110b stretched around of a fixed cylindrical bar 112a, 112b of horizontal axis which causes it to erase a semicircular trajectory. The curved edge 114a, 114b of this endless band is made integral with an endless chain 116a, 116b (or similar) capable of following a semicircular trajectory. This endless chain is stretched between two pinions 117a, 117b coaxial with the cylindrical bar 112a, 112b, one of these pinions being rotated by a motor 118a, 118b. These motors 118a, 118b are synchronized to control the same speed of rotation to the two endless belts of the curved conveyor portions.

The curved portions 102a, 102b of the conveyor are spaced apart from each other so as to arrange between them a radial slot 120 to enable unwinding the fibrous web 106 positioned on the circular conveyor. A plate 122 covers about half of this spacing between the curved conveyor portions.

The radial slot 120 opens under the circular conveyor 102 of the supply table to a substantially straight trough 400 which extends vertically between the circular conveyor and the needling table 200. This chute has the function of taking up the sheet 106 which is unrolled from the conveyor and guide vertically on the needling table.

For this purpose, as shown on the figure 2 , the inlet 402 of the chute 400 is slightly angularly offset (in the direction of rotation of the circular conveyor 102) relative to the slot 120. Advantageously, a conical roller 124 is disposed under the circular conveyor 102 which it is secured and angularly interposed between the slot 102 and the inlet 402 of the chute 400. This roller thus makes it possible to take up a free end of the fibrous web 106 unwound from the conveyor and to guide it towards the inlet of the chute.

The right chute 400 is in the form of a hollow tubular duct extending vertically from its inlet 402 opening under the circular conveyor 102 to its curve outlet 404 whose contour matches the curvilinear profile of a support plate 202 of the needling table (see figure 4 ). The latter is centered on the vertical axis 104 and receives the fibrous web fed by the chute from the feed table.

The fibrous web thus fed onto the support plate 204 is rotated about the vertical axis 104 in the same direction of rotation. rotation as the circular conveyor to pass under a needling head described later. For this purpose, means for rotating the fibrous web comprise two (or more) pairs of conical rollers which are spaced angularly from one another. Each pair of rollers 204 consists of a conical roll 204a forming a pressure roller in continuous contact with the fibrous web and a conical counter-roller 204b disposed in an opening of the support plate opposite the pressing roller 204a so as to take sandwich the fibrous web. More specifically, the support plate is perforated so that the counter-rollers 204b come directly into contact with the fibrous web deposited on this plate.

The pressure rollers 204a are rotated, for example by means of each of a geared motor unit 206 independent controlled from control means (not shown). The counter-rollers 204b may be freely rotatable or possibly driven. These control means in particular make it possible to synchronize the speeds of rotation of the rollers with one another. Of course, other conventional means of rotation and speed synchronization of the rollers could be envisaged.

The needling table also comprises a guide plate 208 in the form of two annular walls 210 centered on the vertical axis 104 and extending vertically from the support plate 202. These vertical walls are interconnected by reinforcements lateral 212 and allow to provide lateral guidance of the fibrous web during its rotation about the vertical axis.

According to an advantageous arrangement, this guide plate is vertically movable relative to the support plate 202 between a low operating position in which it rests on said support plate to ensure lateral guidance of the fibrous web 106 (FIG. Figure 5A ) and a raised position in which it is positioned above said support plate ( Figure 5B ). In the raised position of the guide plate 208, the textile structure 214 formed from the needled fibrous web can be easily discharged onto the discharge table 300 by subsequent detailed evacuation means.

The vertical displacement of the guide plate 208 is for example provided by means of a jack 216 whose body 216a is integral with the feed table 100 and the rod 216b is fixed on the guide plate. This jack is actuated by control means (not shown). The guide plate is raised by translating around a bar 218 centered on the vertical axis 104 and fixed to the feed table.

In addition, this vertical movement is allowed because the chute 400 has a portion 400a which is integral with the feed table 100 and another portion 400b which is secured to the guide plate 208 of the needling table, these portions 400a, 400b being able to translate one inside the other during movements of the guide plate (in the example of Figures 5A and 5B it is the portion 400b secured to the guide plate which translates inside the portion 400a integral with the feed table during these movements).

It should be noted that the guide plate 208 has an angular cutout 219 corresponding to the shape of the needling head (described below) and allowing the guide plate to pass during its vertical displacements.

According to another advantageous arrangement, the guide plate 208 further comprises a conical pressure roller 220 which is disposed at the outlet of the trough 400. This pressure roller is more precisely positioned just above the fibrous web when it leaves the trough. so as to properly level the fibrous web before passing under the needling head. The two pairs of rollers 204 for rotating the fibrous web and the pressing roller 220 are preferably angularly spaced from each other by about 120 ° ( figure 4 ). Furthermore, this pressure roller being secured to the guide plate, it is able to move vertically with it.

The needling of the fibrous web brought onto the support plate is formed by a needling head 222 comprising a determined number of barbed needles and disposed directly above the support plate between the two pairs of tapered drive rollers 204. in rotation of the tablecloth. In known manner, to allow the needling of each of the various superposed layers of fibrous web, this needling head is driven by a vertical reciprocating movement by means of conventional means of displacement 224. In addition, the support plate 202 of the needling table is vertically movable under the action of motion transmission means 226 as the needling operation progresses.

Cutting means disposed upstream of the needling head are also provided for cutting the web once the predetermined final thickness has been obtained for the textile structure (unrepresented sensors make it possible to precisely control this thickness as and when the superposition of the different layers). As shown on the figure 4 these cutting means may comprise a circular knife 228 movable radially along a gantry 230 carried by the guide plate 208, this gantry being disposed angularly after the pressure roller 220 in the direction of rotation of the fibrous web. Of course, other cutting means can be envisaged.

Once the sheet is cut and the needle-punched structure, evacuation means illustrated on the figure 6 allow to transfer the textile structure on the discharge table 300 for transfer to another position in the production line as a heat treatment station. For this purpose, these evacuation means comprise a manipulator arm 302 extending radially and provided with an articulated finger 304 for gripping and evacuating the textile structure 214 on a plate 306 of the evacuation table. This evacuation operation requires that the guide plate of the needling table is in its raised position as illustrated by the Figure 5B .

It should be noted that central control means (not shown in the figures) are connected to the motors 118a, 118b of the curved conveyor portions of the feed table, to the motion transmission means 226 of the support plate 202 of the table of needling, to the geared motor assemblies 206 of the pairs of tapered rollers 204 driving in rotation of the fibrous web, to the displacement means 224 of the needling head 222, to the cutting means 228, 230 of the fibrous web , and the evacuation means 302, 304 of the textile structure. These central control means make it possible to ensure the control and the synchronization necessary for obtaining a continuous needling process.

Claims (10)

1. A circular needling machine (10) for needling a textile structure formed from a helical fiber sheet, the machine comprising a needling table (200) disposed beneath a feed table (100) for feeding a helical fiber sheet for needling, the machine being characterized in that the feed table comprises a circular belt conveyor (102) for receiving thereon a helical fiber sheet (106) for needling, the conveyor being centered on a vertical axis (104) and having a radial slot (120) opening out under the circular conveyor to unwind continuously the fiber sheet received on the conveyor, the slot opening out under the conveyor towards a substantially straight chute (400) that extends vertically between the conveyor and a support tray (202) of the needling table centered on the vertical axis of the conveyor so as to take up the sheet unwound from the conveyor and bring it onto the needling table, said support tray having means (204, 206) for driving the fiber sheet in rotation about the vertical axis.
2. A machine according to claim 1, wherein the needling table (200) further includes a guide tray (208) centered on the vertical axis and movable vertically relative to the support tray (202) between a low, operating position in which it rests on said support tray, and a raised, disengaged position in which it is positioned above said support tray.
3. A machine according to claim 2, wherein the chute (400) has one portion (400a) secured to the feed table (100) and another portion (400b) secured to the guide tray (208) of the needling table, these portions being suitable for moving in translation one inside the other during the vertical movements of the guide tray.
4. A machine according to any one of claims 1 to 3, wherein the means for driving the fiber sheet in rotation comprise two pairs of conical rollers (204) that are angularly spaced apart from each other and that are designed to come into contact with the fiber sheet brought onto the needling table.
5. A machine according to any one of claims 1 to 4, further comprising a conical presser roller (220) secured to the guide tray (208) of the needling table and placed at the outlet from the chute (400).
6. A machine according to any one of claims 1 to 5, wherein the feed table (100) further includes a roller (124) placed under the circular conveyor (102) and angularly interposed between the slot (120) and the inlet (402) of the chute so as to enable a free end of the sheet being unwound from the conveyor to be taken up and guided towards the chute.
7. A machine according to any one of claims 1 to 6, further including means for removing the textile structure (214) from the support tray (202) of the needling table.
8. A machine according to claim 7, wherein the means for removing the textile structure comprise a manipulator arm (302) provided with a hinged finger (304) for taking hold of and removing the textile structure (214).
9. A machine according to any one of claims 1 to 8, wherein the needling table (200) further comprises cutter means (228, 230) for cutting the fiber sheet.
10. A machine according to any one of claims 1 to 9, wherein the circular conveyor of the feed table (100) has two curved conveyor portions (102a, 102b), each in the form of a half-disk and disposed facing the other, the slot being formed by a gap left between the two conveyor portions.

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