Buffer device for matching the output speed of a lap of a spreading-lapping machine to the input speed of a device for processing the lap downstream of the spreading-lapping machine.

Abstract

Crosslapper, in particular arranged at the outlet from a carding device producing a web of fibers, in particular nonwoven fibers, comprising a front belt carrying the web of fibers in the crosslapper to an infeed or accumulator carriage, a rear belt carrying the accumulated web to a layering carriage and an apron on an upper strand (2; 2; 2) of which the layering carriage deposits the web accumulated by the accumulator carriage alternately on the bias in one direction and in the other direction to form a lap (N) moving at a speed V1(t) that varies as a function of time, in particular in a periodic manner, the crosslapper also comprising an output belt strand (20; 20; 20) on which the lap (N) leaves the crosslapper at a speed V2(t) that is different from the speed V1(t), in particular at a constant speed, the lap (N) undergoing at least one turn between the upper strand (2; 2; 2) and the output belt strand (20; 20; 20), in particular through 180, around a roller (3.2; 4.1; 3.7) mounted such that it can move in translation along the output belt strand (20; 20; 20), the lap (N) being sandwiched between another strand, turned in the opposite direction to the upper strand (2), of the apron and the output belt strand (20) and/or between another strand, turned in the opposite direction to the upper strand (2; 2), of the apron and an upper strand of an intermediate apron (30; 30) and/or between a lower strand of an intermediate apron (30; 30) and the output belt strand (20; 20).

Claims

1. A crosslapper in particular arranged at the outlet of a carding device producing a web of fibers, in particular nonwoven fibers, comprising a front belt carrying the web of fibers in the crosslapper to an infeed or accumulator carriage, a rear belt carrying the accumulated web to a layering carriage and an apron on an upper strand (2; 2; 2) of which the layering carriage deposits the web accumulated by the accumulator carriage alternately on the bias in one direction and in the other direction to form a lap (N) moving at a speed V1(t) that varies as a function of time, in particular in a periodic manner, the crosslapper also comprising an output belt strand (20; 20; 20) on which the lap (N) leaves the crosslapper at a speed V2(t) that is different from the speed V1(t), in particular at a constant speed, the lap (N) undergoing at least one turn between the upper strand (2; 2; 2) and the output belt strand (20; 20; 20), in particular through 180, around a roller (3.2; 4.1; 3.7) mounted such that it can move in translation along the output belt strand (20; 20; 20), the lap (N) being sandwiched between another strand, turned in the opposite direction to the upper strand (2), of the apron and the output belt strand (20) and/or between another strand, turned in the opposite direction to the upper strand (2; 2), of the apron and an upper strand of an intermediate apron (30; 30) and/or between a lower strand of an intermediate apron (30; 30) and the output belt strand (20; 20).

2. The crosslapper according to claim 1, characterized in that the roller (3.2, 4.1, 3.7) is mounted such that it can move in translation in a direction parallel to the upper strand (2; 2; 2), in particular the horizontal direction.

3. The crosslapper according to claim 1, characterized in that said other strand, turned in the opposite direction to the upper strand (2), extends between two rollers (3.2, 3.3), which are mounted such that they can move in a translationally fixed manner, in particular in a back-and-forth movement.

4. The crosslapper according to claim 1, characterized in that the upper strand of the intermediate belt (30; 30) extends between two rollers (4.1, 4.2; 3.7, 3.8) which are mounted such that they can move in a translationally fixed manner, in particular in a back-and-forth movement.

5. The crosslapper according to claim 1, characterized in that the lower strand of the intermediate belt (30; 30) extends between two rollers (4.1, 4.2; 3.7, 3.8) which are mounted such that they can move in a translationally fixed manner, in particular in a back-and-forth movement.

6. The crosslapper according to claim 5, characterized in that the intermediate belt (30; 30) is an endless belt that can be moved in translation in a back-and-forth movement which extends around the two rollers (4.1, 4.2; 3.7, 3.8) that are mounted such that they can be moved in a translationally fixed manner.

7. The crosslapper according to claim 1, characterized in that the output belt is air-permeable and the apron is an air-impermeable belt, in particular an endless belt.

8. The crosslapper according to claim 1, in which the intermediate belt (30; 30) is provided, and characterized in that the intermediate belt (30; 30) is air-permeable.

9. The crosslapper according to claim 1, characterized in that the upper strand (2) of the apron and the output belt strand (20) form part of the same endless belt and the arrangement is such that the lap (N) is sandwiched before the turn, during the turn and after the turn between the endless intermediate belt (30) and said same endless belt.

10. An installation comprising a crosslapper according to claim 1 and a further processing device arranged directly downstream of the crosslapper (1), and having an input belt moving at the speed V2(t)

Description

[0024] By way of example, preferred embodiments of the invention will now be described with reference to the drawings in which:

[0025] FIG. 1 is a side view of an installation according to the invention, the crosslapper being on the right-hand side of the figure, the compensation device being in the center and the further processing device, which is located to the left of the figure, not being shown;

[0026] FIG. 2 is a large-scale view of the compensation machine of the installation in FIG. 1;

[0027] FIG. 3 is a schematic side view of part of a crosslapper according to an embodiment of the invention;

[0028] FIG. 4 is a schematic side view of part of a crosslapper according to another embodiment of the invention;

[0029] FIG. 5 is a schematic side view of part of a crosslapper according to yet another embodiment of the invention;

[0030] FIG. 6 is a schematic side view, partially cutaway, of the crosslapper from FIG. 3;

[0031] FIG. 7 is a schematic side view, partially cutaway, of the crosslapper from FIG. 4; and

[0032] FIG. 8 is a schematic side view, partially cutaway, of the crosslapper from FIG. 5.

[0033] FIGS. 1 and 2 show an embodiment of an installation according to the invention. This comprises a crosslapper 1, delivering, via an output apron 2, a lap of nonwoven fibers consisting of a stack of webs of fibers deposited successively on the bias with respect to the longitudinal displacement direction of the apron 2 by an accumulator carriage (not visible in the figure) of the crosslapper.

[0034] Downstream of the crosslapper 1 and its output apron 2, a compensation machine 3 is provided, said machine receiving the lap of fibers from the apron 2 on an upstream portion 4.1 of an air-permeable lower belt 4, which transports the lap of fibers to a downstream output portion 4.2 of the input belt 4 to feed a further processing device which may, for example, be a needle loom or, as shown in FIG. 1, a tenter followed by a needle loom (not visible in the figure).

[0035] The lower belt 4 is endless and extends around rollers 6.1, 6.2, 6.3, 6.4, 6.5 and 6.6. Of these rollers 6.1 to 6.6, two rollers, 6.3 and 6.6 respectively, are driven by lower 7 and upper 8 motors.

[0036] The lower belt 4 comprises a first substantially horizontal upstream portion extending between the roller 6.1, which is closest to the crosslapper or downstream roller 6.1, to a first upstream roller 6.6, turning through 180, around which it performs a half-turn through 180, then a portion extending to a downstream lower turning roller 6.5 where it performs a half-turn through 180 in the opposite direction to the half-turn performed at the upstream turning roller to thus turn the lap in the same direction in which it entered the upstream inlet portion of the lower belt 4 to a lower portion 4.2 extending to a downstream end roller 6.4. The input belt 4 then comprises a lower portion between the downstream end roller 6.4 and the roller 6.3 driven by the motor 7, then returns along a portion extending between the roller 6.3 and the roller 6.2, where it undergoes a turn to return to the roller 6.1.

[0037] The lap of fibers leaving the apron 2 is supported by the lower belt 4 on the first and third portion or upstream input portion and end downstream output portion, and around the two upstream and downstream turning rollers 6.6 and 6.5.

[0038] The device also comprises an air-impermeable upper belt 9 which is endless and is driven around rollers 6.7, 6.8, 6.9 and 6.10, as well as around rollers 6.5 and 6.6. The upper belt 9 covers the lap and sandwiches it with the belt 4 on part of the first portion of the belt 4, a half-circumference of the upstream turning roller 6.6, the intermediate portion between the two upstream 6.6 and downstream 6.5 turning rollers, a half-circumference of the downstream turning roller 6.5 and part of the downstream end portion 5 of the belt 4.

[0039] The downstream turning roller 6.5 is mounted such that its axis is able to move along rails 12 in a horizontal direction. The speed of the motor 8 of the upstream turning roller 6.6 is controlled such that the input portion of the belt 4 has the same speed as that of the apron 2 of the crosslapper 1. The output speed of the motor 7 driving the downstream roller 6.3 is controlled to achieve a constant speed corresponding to the speed of the input belt of the further processing device, for example the needle loom.

[0040] Thus, the two motors 7 and 8 each rotate at different speeds corresponding to the speed of the output belt 2 of the crosslapper in one case and in the other case 7 to the input speed of the further processing device, in particular the needle loom. The difference between these speeds causes a variation in the length of the portion of the lower 4 and upper 9 belts which extends between the rollers 6.5 and 6.6, and this variation is compensated by the movement of the axes of the rollers 6.5 and 6.2 for the lower belt 4 and by the movement of the axes of the rollers 6.5 and 6.10 for the upper belt 9, the other axes of the rollers being fixed (the rollers are virtually static, not being moved in translation, but merely in rotation in relation to their respective axis)).

[0041] FIGS. 3 and 6 show a crosslapper according to the invention, in which a compensation device is incorporated. The crosslapper in FIGS. 3 and 6 comprises a front belt 303, in particular an endless belt, carrying the web of fibers in the crosslapper to an infeed or accumulator carriage, a rear belt 302 carrying the accumulated web to a crosslapper or removal carriage and an apron 100 on which the layering carriage deposits the web accumulated by the accumulator carriage alternately on the bias in one direction and in the other direction to form a lap moving at a speed V1(t) that varies as a function of time, in particular in a periodic manner. The crosslapper also comprises an output belt by which the lap leaves at a speed V2(t) that is different to the speed V1(t), in particular at a constant speed. The crosslapper comprises an apron 100 on an upper strand 2 of which the web is deposited in a plurality of layers in a zigzag pattern by the removal carriage to form a lap N, the apron 100 being driven around four rollers 3.1, 3.2, 3.3 and 3.4, at least one of which is a motor. An air-permeable endless belt forms an output belt 200 of the crosslapper on an upper strand 20 of which the lap leaves the crosslapper. This endless output belt 200 is shown in a schematic manner and is driven in the same manner by rollers which rotate at a constant speed or synchronized with the further processing device. The lap N undergoes a turn around the roller 3.2 to be sandwiched between a lower strand, opposite the upper strand 2, of the air-impermeable apron and the upper strand 20 of the output belt.

[0042] The axes of the two upper rollers 3.1 and 3.4 are mounted such that they are fixed whereas the axes of the rollers 3.2 and 3.3 are mounted such that they can move in a horizontal translationally fixed manner in a back-and-forth movement to thus adapt the displacement speed of the lap passing from the strand 2, which has a speed that varies as a function of time, to the strand 20, which has a speed, in particular constant, equal to the speed of the input belt of the further processing device. During the back-and-forth movement of the rollers 3.2 and 3.3, the endless belt forming the apron 100 maintains a constant overall length.

[0043] FIGS. 4 and 7 show another embodiment. The crosslapper in FIGS. 4 and 7 comprises a front belt 303, in particular an endless belt, carrying the web of fibers in the crosslapper to an infeed or accumulator carriage, a rear belt 302 carrying the accumulated web to a crosslapper or removal carriage and an apron 100 on which the layering carriage deposits the web accumulated by the accumulator carriage alternately on the bias in one direction and in the other direction to form a lap moving at a speed V1(t) that varies as a function of time, in particular in a periodic manner. The crosslapper also comprises an output belt by which the lap leaves at a speed V2(t) that is different to the speed V1(t), in particular at a constant speed. The upper strand 2 of the apron 100 in the form of an air-impermeable endless belt is driven around rollers 3.1, 3.2, 3.3 and 3.4 with fixed axes, at least one of which is a motor. An air-permeable intermediate endless belt 30, arranged between the apron 100 and a strand 20 of an output belt 200 is provided, the intermediate belt 30 being driven between two rollers 4.1 and 4.2, at least one of which is preferably a motor. The axes of the rollers 4.1 and 4.2 are mounted such that they can move in a translationally fixed manner in the horizontal direction in a back-and-forth movement to thus adapt the displacement speed of the lap passing from the upper strand 2, which has a speed that varies as a function of time, to the upper strand 20 of the output belt, which has a speed, in particular constant, equal to the speed of the input belt of the further processing device.

[0044] In this embodiment, the lap N is subjected to a turn around the roller 4.1. Before the turn, it is sandwiched between a lower strand of the apron, which is turned in the opposite direction to the upper strand 2, and an upper strand of the intermediate belt 30. After the turn, it is sandwiched between the upper strand 20 of the output belt and a lower strand of the intermediate belt 30. The lower strand of the intermediate belt 30 is turned in the opposite direction to the upper strand of the intermediate belt 30. During the back-and-forth movement of the rollers 4.1 and 4.2, the endless belt forming the intermediate belt maintains a constant overall length.

[0045] Finally, FIGS. 5 and 8 show a third embodiment. The crosslapper in FIGS. 5 and 8 comprises a front belt 303, in particular an endless belt, carrying the web of fibers in the crosslapper to an infeed or accumulator carriage, a rear belt 302 carrying the accumulated web to a layering 304 or removal carriage and an apron 100 on which the layering carriage 304 deposits the web accumulated by the accumulator carriage 301 alternately on the bias in one direction and in the other direction to form a lap moving at a speed V1(t) that varies as a function of time, in particular in a periodic manner. The crosslapper also comprises an output belt (which, in this embodiment, is part of the apron 100) by which the lap leaves at a speed V2(t) that is different to the speed V1(t), in particular at a constant speed. An upper strand 2 of an apron 100 in the form of an air-impermeable endless belt extends around rollers 3.1 to 3.7, the upper strand 2, on which the lap N is deposited by the layering carriage, extends between two upper rollers 3.1 and 3.4. The lap N undergoes a first turn around the upper turning roller 3.3 and is then sandwiched between an intermediate upper strand, which is turned in the opposite direction to the upper strand 2 of the apron, which extends between the upper turning roller 3.3 and a lower turning roller 3.7, and an upper strand of an endless intermediate belt 30 which extends around the roller 3.7 and a roller 3.8. The lap then undergoes a second turn through 180 around the lower turning roller 3.7 in an opposite direction to the first turn, to then be supported by a lower strand 20 of the apron output belt extending between the turning roller 3.7 and a lower roller 3.6 at the downstream end, the lap leaving the crosslapper on the lower output strand 20.

[0046] The upper strand of the intermediate belt 30 sandwiches the lap with the intermediate upper strand of the apron 2 between the two turning rollers, 3.3 and 3.7 respectively, then the lower strand of the intermediate belt 30 sandwiches the lap with the lower strand 20 of the output belt of the apron between the turning roller 3.7 and a roller 3.8 at the downstream end of the intermediate belt 30. The intermediate belt 30 is air-permeable and is driven around the two rollers 3.7 and 3.8, which are mounted such that they can move in a translationally fixed manner in a back-and-forth movement such that their axes move in translation to adapt the displacement speed of the lap passing from the upper strand 2 of the apron 200, which has a speed that varies as a function of time, to the lower strand 20 of the apron 200, which has a speed, in particular constant, equal to the speed of the input belt of the further processing device.

[0047] The lap is sandwiched between the apron and the intermediate belt 30 before the second turn, during the second turn, around the roller 3.7 and after the second turn, and is thus well protected from the harmful effects of drive and/or centrifugal forces associated with displacements of the rollers 3.7 and 3.8 in translation and in rotation.

[0048] In the embodiments in FIGS. 4 and 5, it is conceivable that the intermediate belts, 30 and 30 respectively, could be turned in the opposite direction so that the lap can be turned or not be turned as a function of the thickness of the lap. If there is no need for the lap to be turned, in particular in the case of very thick laps, for example in excess of 150 mm, the belts 30 and 30 are turned in the opposite direction to that described in the figures and the lap is deposited directly on the strand 20, or 20 respectively, of the output belt, after cascading over the rollers 3.3 and 4.2 respectively in the case of FIG. 4 and the rollers 3.3 and 3.8 in the case of FIG. 5.

[0049] In the embodiment in FIG. 3, it is conceivable to use two outlets, one on the right as shown, in particular for laps which are not very thick, for example which are less than or equal to 150 mm thick, and an outlet directly to the left without passing beneath the apron, in the case of thick laps, in particular those which are between 300 and 500 mm thick.

[0050] FIGS. 6 to 8 are partially cutaway to show the input and output belts and the infeed and removal carriages.