EP3141640A1 - Cross-lapper and method for controlling such a cross-lapper - Google Patents

Abstract

Spreader-laparer, in particular arranged at the exit of a card device producing a web of fibers, in particular of non-woven material, comprising a carpet (2) before bringing the web (4) of fibers into the crosslapper up to an accumulator carriage (12), in particular moving in a reciprocating motion; a mat (5) rear bringing the accumulated veil to a trolley (9) lapper, including also moving in a back and forth motion; and an apron (3) output, the accumulator carriage being arranged to return the fiber web to the lapper carriage, and the latter being arranged to deposit the accumulated veil and returned by the accumulator carriage on the apron at an angle to obtain a tablecloth composed of layers which are obliquely, alternately in one direction and in the other, with respect to the lengthwise direction of the ply (6), the front and rear conveyor belts (2) being driven by rollers (2i , 5i) respective front and rear drive. Anti-slip means for preventing relative slippage of at least one of the front and rear mats (2) relative to its respective driving roller is provided.

Description

The present invention relates to a spreader-spreader device intended to cover a web of fibers, in particular nonwoven fibers, in particular at the exit of a card device, as well as to a method for controlling a crosslapper of this type. kind.

Conventionally, a crosslapper disposed at the exit of a card device producing a fleece of nonwoven fibers comprises a front mat bringing the web of fibers into the spreader-lapper to a moving storage trolley according to a movement back and forth, a back carpet bringing the accumulated web to a lapper carriage also movable in a back and forth motion and an exit apron, the accumulator carriage being arranged to return the fiber web to the lapper carriage, and the latter being arranged to deposit the accumulated veil and returned by the accumulator carriage on the apron to obtain a sheet of layers which are obliquely, alternately in one direction and the other, with respect to the direction in length of the tablecloth.

The characteristics of the web that one wishes to obtain (grammage, surface density, orientation of the folds, length of the folds, etc.) are regulated in advance on the basis of the settings of the entry speeds of the veil, speeds and races. moving carriages back and forth, and generally kinematic data of the components of the lapper spreader. The spreader-lapper devices known from the prior art have the disadvantage that defects of uniformity compared to the characteristics set in advance appearing here and there on the final tablecloth. This is particularly the case when trying to increase production speed by using more powerful engines.

Of FR2791364 , EP0522893 and EP 1816243 such crosslappers are known and have the features of the preamble of claim 1.

Once the characteristics of the sheet which one wishes to obtain have been set, the present invention aims at a lapping spreader making it possible to obtain a sheet which is as uniform as possible with respect to these characteristics set in advance, and preferably in the speed range. of the highest possible production.

According to the invention, a spreader-lapper, in particular arranged at the exit of a card device producing a web of fibers, in particular non-woven fibers, comprising a front carpet bringing the fiber web into the crosslapper up to an accumulator carriage, in particular moving in a reciprocating motion; a rear carpet bringing the accumulated web to a lapper carriage, in particular also moving in a back and forth motion; and an output apron, the accumulator carriage being arranged to return the fiber web to the lapper carriage, and the latter being arranged to deposit the accumulated veil and returned by the accumulator carriage to the apron at an angle, alternately in a direction and in the other, with respect to the lengthwise direction of the web, the front and rear mats being driven by rollers respective front and rear drive means, is characterized by anti-slip means for preventing relative sliding of at least one of the front and rear mats relative to its respective roller, especially rear, preferably both front mats. and back.

The inventor of the present invention has understood that the defects of uniformity with respect to the characteristics set in advance appearing on the sheet obtained at the output of the crosslapper are due to uncontrolled speed differentials between the front mat and the rear carpet in particular in the course of the sail between the accumulator carriage and the lapper carriage where the web is supported by the rear carpet and capped by the front carpet, and at speed differentials between the means bringing the card web and the carpet before taking it up and speed differentials between the rear carpet bringing the sail into the lapper carriage and the speed of the latter laying the web on the web forming the lapper output, each of these causes of failure is induced in particular by sliding phenomena between the front carpet or the rear carpet and its control roller during the acceleration or deceleration phases of the upholstery s intervening in particular at each inversion of the movement of the topping carriage. As the accelerations and decelerations of the mats increase with the entry speed of the lapper, the defects induced by these sliding phenomena are accentuated with the speed of production.

Providing means whose function is to prevent the relative slippage of the front and / or rear mats relative to the respective drive roller, this results in output as a result a web without defect with respect to the web that is expected to obtain compared to the prerequisite settings of the crosslapper. In addition, the slip no longer exists, it is possible to increase the production rate of the web of the spreader-lapper without decreasing the quality of the obtained web and / or it can be predicted, for the same flow rate, that at present use a drive motor control motor lighter and / or less powerful and thus reduce the final cost of the nonwoven web.

According to a particularly advantageous embodiment of the invention, which is particularly advantageous, the anti-slip means consist of at least one auxiliary drive roller associated with an auxiliary motor, which applies a complementary actuating force to the respective drive roller. said at least one of the front and rear mats, itself driven by a respective main motor.

By thus providing an auxiliary drive roller in addition to the main drive roller, it facilitates the fine adjustment of the movement of the belt relative to the sail, in particular by avoiding having to spend the effort necessary to accelerate any the length of the carpet in a single control point and thus increase the risk of slippage between the carpet and its control roller during strong accelerations.

The or each auxiliary drive roller is driven by an auxiliary motor, preferably controlled in torque. The or each main driving roller is driven by a main motor, preferably speed controlled.

In particular, the torque of the or each auxiliary motor is controlled as a function, in particular proportionally, of the acceleration of the lapping carriage and as a function of the lapping cycles (forward acceleration, forward deceleration, return acceleration, reverse deceleration) so as to relieve the main engine in these phases of acceleration and deceleration thus reducing the effort to be transmitted between the main drive roller and the belt.

The present invention also relates to a method for controlling a spreader-spreader comprising a front mat, an accumulator carriage, a rear mat, a lapper carriage and an apron, the speeds and displacements of the various elements of the lapper spreader being adjusted to advance to obtain a mat having predetermined characteristics, the front mat being driven by a front drive roller driven by a front main motor and the rear mat being driven by a rear drive roller driven by a rear main engine, is characterized by the step of providing anti-slip means for canceling the sliding between at least one of the front and rear carpet and its respective drive roller, including at least one roller of auxiliary drive, particularly driven by a torque-controlled auxiliary motor.

la figure 1

est une vue en perspective schématique d'un étaleur-nappeur suivant l'invention ;

la figure 2

est une vue en coupe schématique de l'étaleur-nappeur de la figure 1 dans un plan perpendiculaire au plan de la nappe déposée sur le tablier, le chariot nappeur se trouvant dans une position entre la position d'extrémité droite ou avant de dépôt lors du cycle de nappage et une position gauche ou arrière par rapport à la nappe déposée sur le tablier de l'étaleur-nappeur.

By way of example, a preferred embodiment of the invention will now be described with reference to the following drawings in which:

Figure 1

is a schematic perspective view of a spreader-lapper according to the invention;

Figure 2

is a schematic sectional view of the crosslapper of the figure 1 in a plane perpendicular to the plane of the sheet deposited on the deck, the lapper carriage being in a position between the right end position or before deposit during the lapping cycle and a left or rear position relative to the deposited web on the apron of the spreader-lapper.

In the figures, there is shown a spreader-lapper 1 according to one embodiment of the invention. This lapping spreader is disposed downstream of a card producing a nonwoven web that arrives on a mat 2 before endless. The front endless belt 2 comprises a section 21 rising slope followed by a horizontal section extending to a trolley 12 accumulator. The endless conveyor belt then comprises several sections in succession, in particular the sections 22, 23, 25, 26, 27 and 29 before returning to the section 21. According to a variant shown but not essential to the invention, a simple embodiment is provided. 2d detour roll around which the carpet 2 before performs a half turn, the rear carpet 5 recovering the web 4 after flipping the sail to transport it to the lapper carriage 9.

The movements and / or displacements of the carriages 9 and 12 and the belts 5 and 2 are controlled by a central unit which controls their respective motor according to the desired kinematic data (positions, speeds, acceleration) for each, these settings defining the parameters (including length, orientation bias folds and surface density) desired for the final web.

The two carpets 2 and 5 are endless carpets that run in opposite directions from each other. The inlet belt 2 is guided along its travel path by rollers 2a to 2n. The rear carpet 5 is guided along its path by rollers 5b to 5n. The rollers are freely rotatable, except those connected to motor means, as described in the present application.

Preferably, the two mats are driven so as to have in the overlapping area of the web (between the two carriages and up to the apron, in particular in the vertical passage 17 just before the site 11 of deposit on the sheet lying on the apron 3 (driven by rollers, including the roller 3a), equal speeds corresponding to the desired speed of supply of the web 4 at the site 11 deposition.

The rear carpet 5 makes a 180 ° turn around the roll 5g after the area 52 overlap / nip of the web by the two mats 2 and 5. To prevent compression of the web in the lapper carriage, including the transition between the part 42 and the deposition area 11, the carpet 2 input is diverted around a detour roll 2f.

The lapper carriage moves back and forth in the horizontal direction in the figure. During this movement, the belt 5 undergoes a variation in its length (substantially equal to twice the displacement in one direction given the carriage 9). It is therefore necessary to provide compensation for this variation, which is achieved by the fact that the rear mat performs a 180 ° turn around a roller 51 carried by a compensating carriage 16 moving back and forth in synchronization with the movement of the carriage 9. Thus, regions 56 and 57 of the belt 5 shorten when the regions 52, 53 and 59 of the belt 5 increase and vice versa. To achieve synchronization, there is provided a toothed belt 76 fixed at one end to the lapper carriage and at the other end to the carriage 16, the belt 76 meshing with a driving pulley 77 connected to a motor with two directions of travel, controlled by speed. On the other hand, an inextensible cable 78 connects the other two sides of the carriages 9 and 16.

An identical arrangement is made to synchronize the movement of the accumulator carriage and the length of the entrance belt 2. The belt 2 makes a 180 ° turn around a roller 21 carried by a compensating carriage 14 moving back and forth in synchronization with the movement of the carriage 12. Thus, regions 26 and 27 of the belt 2 are shortened when the regions 21, 22 and 23 of the carpet 2 increase and vice versa. To achieve synchronization, there is provided a toothed belt 71 fixed at one end to the carriage 12 of accumulation and at the other end to the carriage 14, the belt 71 meshing with a driving pulley 72 connected to a motor with two directions of operation , controlled in speed. On the other hand, an inextensible cable 73 connects the other two sides of the carriages 12 and 14.

Each of the belts 2, 5 passes over a respective motor roller 2i, 5i connected to a respective motor 74, 79 controlled by speed (servo motor, stepper or similar). Two return rollers, 2h, 2j and 5h, 5j are arranged on either side of the drive rollers 2i, 5i, in order to maximize the winding of the belt around its control roller and therefore its adhesion.

The drive motors 74, 79 and the motors of the pulleys 72, 77 are controlled (by the CPU not shown) to adapt them to the desired characteristics of the final product to be obtained (length, surface density, etc.) which depend in particular on the speed of entry of the web and / or the travel of the lapper carriage and / or accelerations of the trolleys, and / or others.

A complementary motor 101 acts on the carpet 2 before. It operates a 2m drive roll, which is lined with an adherent coating and is preferably associated with a detour roller 2n to increase the winding of the belt around the roller 2m. The motor roller 2i and the complementary motor roller 2m are placed relatively far from each other along the path of the belt to distribute as much as possible the tensile stresses, especially during the acceleration phases.

The complementary motor 101 is, according to a preferred embodiment, controlled in torque, in particular for each point of the lapping cycle of the crosslapper.

The torque of the complementary motor is controlled to prevent relative sliding between the front belt 2 and the roller 2i motor.

A complementary motor 111 acts on the rear mat. It actuates a drive roll 5m, which is preferably lined with an adherent coating and associated with a detour roll 5n to increase the winding of the carpet around the roll 5m. The motor roller 5i and the complementary motor roller 5m are placed relatively far apart from each other along the path of the belt to distribute as much as possible the tensile stresses, especially during the acceleration phases.

The complementary motor 111 is preferably controlled in torque, in particular for each point of the lapping cycle of the crosslapper.

The torque of the complementary motor is controlled to prevent relative sliding between the belt 5 and the roller 5i motor.

In particular, the complementary engines make it possible to improve the behavior of the lapping spreader by canceling on the one hand the slipping of mats on their control rollers and on the other hand by limiting the variations of tension in the mats during the phases of acceleration and deceleration thanks to the two-point control of each carpet. This fights the effects of carpet slippage on the tablecloth. In addition, either lighter and / or stronger main motors can be used than if there is only one motor per belt, or higher working speeds, in particular by greatly reducing the wear of the mats. by a better distribution of the tensile stresses acting on the mats.

A topping cycle can be as follows: We start from a situation where the lapper carriage is at the end of its front side stroke.

The carriage 9 is then at a standstill while the carriage 12 moves at a constant speed towards the rear to lengthen the regions 21 and 22 of the belt 2. The speed V74 of the main motor 74 of the belt 2 is zero because the regions 22 and 23 are motionless. The speed V12 of the carriage 12 is equal to half the entry speed of the sail 4. The speed of the region 52 of pinching of the belt 5 is zero because equal to the speed of the region 22 of the belt 2. The speed of the regions 58 and 59 is zero. The speed V111 of the engine 111 is zero. The speed V79 of the engine 79 is twice the speed of the lapper carriage.

The torque of the motors is defined as being positive, which makes it possible to accelerate in the direction of the product the belts 2 and 5. figure 2 , the motor pairs 74 and 101 are therefore defined as being positive in the counterclockwise direction while the motor pairs 79 and 111 are defined as positive in the clockwise direction.

In a first phase P1, the lapper carriage accelerates backward (to the left at the figure 2 ), starting his movement to go. The speed of the sections 52, 57, 58 and 59 remain zero while the sections 53 to 56 undergo an acceleration equal to 2 times that of the lapper carriage 9 and its compensating carriage 16. Due to the acceleration of the sections 55 and 56 as well as the compensator carriage 16 on the one hand and the need to maintain the zero speed in the sections 52, 57, 58 and 59, the application of a positive torque in the motor 111 yet at zero speed allows s' to oppose the tension induced by the acceleration of the sections 58, 59 and 52 as well as by the acceleration in rotation of the rollers 5j, 5k and 51 which they induce. The positive torque applied by the motor 111, yet at zero speed, thus relieves the engine 79 while reducing the voltage induced by these accelerations in the sections 58, 59 and 52. In this phase P1, the entire circuit of the carpet before 2, only the rollers 2e, 2f and 2g undergo an acceleration induced by the acceleration of the carriage 9, which implies that a positive non-zero torque is applied by the motor 74 in order to maintain zero the speed of the sections 22 and 23. The torque applied by the motor 101 may then be zero or simply contribute to opposing the rotational friction of the roller 21.

In a second phase P2, the carriages are at a constant speed, all the drive couples being low.

This phase ends beyond the middle of the course of the lapper carriage 9 and in particular beyond the last third of its race to enter a phase P3 of deceleration of the carriage 9 to its stop at the end of the race to go. The speed of the sections 52, 57, 58 and 59 remain zero while the sections 53 to 56 undergo a deceleration equal to 2 times that of the lapper carriage 9 and its compensating carriage 16. Due to the deceleration of the sections 53 to 56 and that the lapper carriage 9 on the one hand and the need to maintain the zero speed in the sections 52, 57, 58 and 59, the application of a negative torque in the motor 111 yet at zero speed allows to oppose the voltage induced by the deceleration of the sections 52 and 53 as well as by the rotational deceleration of the rollers 5g and 5h that they induce. The negative torque applied by the motor 111, yet at zero speed, thus relieves the motor 79 while reducing the voltage induced by these accelerations in the sections 57, 56 and 55. In this phase P3, the entire circuit of the carpet before 2, only the rollers 2e, 2f and 2g undergo a deceleration induced by the deceleration of the carriage 9, which implies that by applying a non-zero negative torque in the engine 101, however, at a constant speed, the engine 74 can be relieved and reduced the induced voltage in the sections 25, 26 and 27.

In phase P4, the lapper carriage 9 accelerates toward the entrance (to the right at the figure 2 ) beginning the return phase. At the same time, the accumulator carriage which had remained at a constant speed during the phases P1 to P3 starts its deceleration until it stops and then reverses.

On the front carpet circuit 2, during this phase P4, all the rolls except 2m, 2n, 2a and 2b and all the sections of carpet except 27 and 21 undergo an acceleration or deceleration induced by the combination of the movements of the accumulator and lower carriages so that the optimum torque to be applied to the motor 101 may vary depending on the inertia of the different rollers. The engine 101 can indeed contribute to the deceleration of the rollers 2c and 2d induced by the deceleration of the accumulator carriage 12 but also to the acceleration of the rollers 2j to 21 induced by the need to accelerate the section 42 of the sail and thus the section 22 to twice the acceleration of the lapper carriage 9 in order to maintain a speed of delivery of the web at point 11 equal to the speed of the lapper carriage 9.

During this same phase P4, on the circuit of the rear carpet, the sections 53 to 56 and the rollers 5h to 5k are at zero speed. The carpet section 52 and the rollers 5m, 5n and 5b undergo an acceleration equal to 2 times that of the carriage 9 in order to feed it, while the rollers 5c to 5f, as well as 51, undergo a combination between 2 times the accelerating the lapper carriage 9 and the deceleration of the accumulator carriage 12. Thus, although at the stop the motor 79 will apply a positive torque opposing the movement of the section 53 induced by the accelerations of the rollers 5b to 5g. At the same time, a positive torque on the engine 111 will assist the engine 79 by contributing in particular to the acceleration of the roller 51 and thus to the reduction of the induced voltages in the sections 58, 59, 52 and 53.

In a fifth phase P5, the carriages are at a constant speed, all the drive couples being low.

This phase ends beyond the middle of the course of the lapper carriage 9 and in particular beyond the last third of its race to enter a phase P6 of deceleration of the carriage 9 until its end at the end of the return stroke. The speed of the sections 53, 55 and 56 remain zero while the sections 52 and 57 to 59 undergo a deceleration equal to 2 times that of the lapper carriage 9 and its compensating carriage 16. Due to the deceleration of the sections 52, 57 and 59 and the lapper carriage 9 on the one hand and the need to maintain the zero speed in the sections 53, 55 and 56, the application of a negative torque in the motor 79 yet at zero speed makes it possible to oppose the voltage induced by the deceleration of the sections 53, 55 and 56 as well as by the deceleration in rotation of the rollers 5b at 5g and 51 at 5n which they induce. The negative torque applied by the motor 111 thus relieves the motor 79 while reducing the voltage induced by these accelerations in the sections 57, 56 and 55. In this phase P6, of the entire circuit of the front carpet 2, all the rollers except 2m, 2n, 2a and 2b and all the sections of carpet except 27 and 21 undergo an acceleration or deceleration induced by the combination of the movements of the accumulator and lower carriages so that the optimum torque to be applied to the motor 101 may vary depending inertia of different rollers. The engine 101 can indeed contribute to the acceleration of the rollers 2c and 2d induced by the acceleration of the accumulator carriage 12 but also to the deceleration of the rollers 2j to 21 induced by the need to decelerate the section 42 of the sail and therefore the section 22 at twice the deceleration of the lapper carriage 9 in order to maintain a speed of delivery of the web at point 11 equal to the speed of the lapper carriage 9.

In the present application, a preferred auxiliary anti-slip means is an auxiliary drive roller associated with an auxiliary drive roller (2m, 5m) associated with a motor (101; actuating complementary to the respective driving roller of said at least one of the front and rear mats, itself driven by a respective main motor (74; 79). However, it goes without saying that the present invention is not limited to this embodiment and that other anti-slip means may be provided, for example an anti-slip coating, anti-slip rolls, perforated or toothed mats or the like without departing from the scope of protection of the invention which is defined by the claims , especially claims 1 and 7.

Claims (8)

Spreader-laparer, in particular arranged at the exit of a card device producing a web of fibers, in particular of non-woven material, comprising a carpet (2) before bringing the web (4) of fibers into the crosslapper up to an accumulator carriage (12), in particular moving in a reciprocating motion; a mat (5) rear bringing the accumulated veil to a trolley (9) lapper, including also moving in a back and forth motion; and an apron (3) output, the accumulator carriage being arranged to return the fiber web to the lapper carriage, and the latter being arranged to deposit the accumulated veil and returned by the accumulator carriage on the apron at an angle, alternately in a direction and in the other, with respect to the lengthwise direction of the web (6), the front and rear conveyor belts (2) being driven by respective front and rear drive rollers (2i, 5i), characterized by anti-slip means for preventing relative slippage of at least one of the front and rear mats (2) relative to its respective, particularly rear, drive roll (2i, 5i) by preferably both front and rear mats (2, 5). Spreader according to Claim 1, characterized in that the anti-slip means prevent relative sliding of the front and rear mats (2, 5) with respect to their respective control roller (2i, 5i). Spreader according to Claim 1, characterized in that the anti-slip means consist of at least one auxiliary drive roller (2m, 5m) associated with an auxiliary motor (101; 111), which applies a force of actuating complementary to the respective driving roller of said at least one of the front and rear mats, itself driven by a respective main motor (74; 79). Spreading machine according to Claim 3, characterized in that the or each auxiliary drive roller is driven by a torque-controlled auxiliary motor. Spreader according to one of claims 3 or 4, characterized in that the main motor (74; 79) is speed-controlled. Spreading machine according to one of claims 3, 4 or 5, characterized in that the torque of the or each auxiliary motor is controlled in function, in particular proportionally, of the acceleration of the lapper carriage and as a function of the lapping cycles of in order to relieve the main motor in the acceleration and deceleration phases thus reducing the effort to be transmitted between the main drive roller and the belt. A method for controlling a crosslapper comprising a front carpet, an accumulator carriage, a rear carpet, a lapper carriage and an apron, the speeds and displacements of the various elements of the lapper-spreader being set in advance to obtain a sheet having characteristics given in advance, the front belt being driven by a front driving roller driven by a front main motor and the rear belt being driven by a rear driving roller driven by a rear main motor, is characterized by the step of providing means anti-slip means for canceling the sliding between at least one of the front and rear conveyor and its respective drive roller, in particular at least one auxiliary drive roller, in particular driven by a torque-controlled auxiliary motor. Method according to Claim 7, characterized in that the anti-slip means comprises at least one drive roller driven by a torque-controlled auxiliary motor.

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