Installation forming a needling machine for needling a sheet or a veil of fibers, in particular non-woven

Abstract

Needle-punching installation for needling a web or a veil of fibers, in particular non-woven. Needle-punching installation comprises a needle board comprising a field of needles and means for driving the needles in a back and forth movement, in particular in the vertical direction, so that the needles, in one direction of movement, penetrate into a web or a veil of fibers, in particular non-woven, to pass through it in a transverse direction, in particular perpendicular, to the direction in which the web or the veil of fibers moves in front of the needles, then in a second direction of movement, emerge from the web or the veil of fibers, fiber dust accumulating on the board between the needles,and the installation further comprising a stripper plate which is pierced with a field of through holes and which is crossed by the needles before they penetrate the web or the sheet of fibers, characterized in that means are provided for monitoring the fiber dust accumulating on the board between the needles. Figure for the abstract: Fig. 1,

Description

Title of the invention: Installation forming a needling machine for needling a sheet or a veil of fibers, in particular non-woven

[0001] The present invention relates to a needling machine installation comprising a needle board whose needles perform a back and forth movement inside a sheet or a veil of fibers, in particular non-woven, passing in front of them, with a view to consolidating it. The present invention also relates to a method of operating an installation of this type.

[0002] In needling installations, it is desired to be able to continually increase the production rate, and in particular to avoid untimely interruptions of the needling line.

[0003] The present invention aims to overcome the drawbacks of the prior art by providing a needling machine installation which makes it possible to increase the production rate of consolidated sheet or web, in particular by avoiding untimely interruptions of the line.

[0004] According to the invention, a needling machine installation comprises a needle board comprising a field of needles and means for driving the needles in a back-and-forth movement, in particular in the vertical direction, so that the needles, in one direction of movement, penetrate into a web or a sheet of fibers, in particular non-woven, to pass through it in a transverse direction, in particular perpendicular, to the direction in which the web or the sheet of fibers moves in front of the needles, then in a second direction of movement, fiber dust emerges from the sheet or the sheet of fibers, fiber dust accumulating on the board between the needles, and the installation further comprises a plate forming a stripper which is pierced with a field of through holes and which is passed through by the needles before they penetrate into the web or the sheet of fibers,is characterized in that means are provided for monitoring the fiber dust accumulating on the board between the needles, in particular means for monitoring the thickness of the layer of fiber dust accumulating on the board between the needles, for example means for measuring the thickness of the layer of fiber dust accumulating on the board between the needles.

[0005] The inventors of the present invention have realized that long-term blockages of the line are often due to fiber dust accumulating between the needles on the face of the board from which they protrude, this dust, by accumulating, forming clumps which can cause the breakage of one or more components of the installation, which leads to the shutdown of the installation for long periods. durations, for example when the needles pass through a stripper plate, strike the stripper plate and subject it to excessive vibrations and / or deformations causing the stripper to break, resulting in a long-term blockage of the production line.

[0006] Thus, when the monitoring means detect that a lot of fiber dust has accumulated between the needles, the user, or automatically, the control system of the installation, can intervene to clean the interstices between the needles before a long-term blockage of the line occurs, and the flow rate and / or the rate of the needling line is thus greatly improved.

[0007] According to an advantageous embodiment, the means for monitoring the fiber dust comprise means for monitoring, in particular for measuring, the vibrations and / or deformations of the stripper plate.

[0008] According to a first advantageous embodiment, the means for monitoring, in particular for measuring, the vibrations and / or deformations of the stripper plate comprise an accelerometer sensor, in particular arranged on the stripper plate.

[0009] According to another favorable embodiment, the means for monitoring, in particular for measuring, the vibrations and / or deformations of the stripper plate comprise means for monitoring, in particular for measuring, the stresses exerted on the fixing and / or support points of the stripper plate.

[0010] According to a first embodiment, the movement of the needles takes place along a rectilinear trajectory.

[0011] According to another embodiment, the movement of the hands takes place along an elliptical trajectory.

[0012] According to one embodiment, alert means are provided capable of giving an alert when the quantity of accumulated fiber dust monitored, in particular the thickness of the layer of accumulated fiber dust monitored, in particular measured, exceeds a threshold value determined in advance.

[0013] In particular, the alert means give the alert when the difference between the vibrations and / or deformations monitored over time and the vibrations and / or deformations when empty exceeds a threshold value determined in advance.

[0014] According to a preferred embodiment of the invention, the means for monitoring the vibrations and / or deformations of the stripper plate measure the deformations and / or vibrations of the stripper plate when empty, called reference vibration and / or deformation, corresponding to the case where no fiber dust is present between the needles, and comparison means are provided capable of comparing the vibrations and / or deformations of the stripper plate measured by means of monitoring over time the reference vibrations and / or deformations.

[0015] According to one embodiment, means are provided for removing fiber dust between the needles.

[0016] In particular, control means, in particular electronic, may be provided which actuate the warning means and / or the dust elimination means when it is detected that the quantity of fiber dust, in particular the thickness of the layer of fiber dust, exceeds a threshold value determined in advance, in particular when a variation in the vibrations and / or deformations of the stripper plate is detected, in particular when they exceed a threshold value.

[0017] According to another embodiment, the monitoring means comprise a camera, in particular an electronic camera, which monitors the quantity of fiber dust, in particular the thickness of the layer of dust, formed between the needles.

[0018] According to yet another embodiment, the monitoring means comprise a camera, in particular an electronic one, which monitors the deformations and / or vibrations of the stripper plate.

[0019] The present invention also relates to a method of operating a needling machine installation comprising a needle board comprising a field of needles and means for driving the needles in a back and forth movement, in particular in the vertical direction, so that the needles, in one direction of movement, penetrate into a web or a sheet of fibers, in particular non-woven, to pass through it in a transverse direction, in particular perpendicular, to the direction in which the web or the sheet of fibers moves in front of the needles, then in a second direction of movement, fiber dust emerges from the sheet or the sheet of fibers, accumulating on the board between the needles, in which: - we monitor the fiber dust that accumulates on the board between the needles, and - when the quantity of fiber dust monitored exceeds a threshold value, means are implemented to eliminate the fiber dust accumulated on the board.

[0020] According to one embodiment, the implementation of the elimination means is carried out after having stopped the operation of the installation.

[0021] According to another embodiment, the implementation of the elimination means is carried out automatically, without stopping the operation of the installation.

[0022] By way of example, an embodiment of the invention will now be described with reference to the drawings, in which:

[0023] [Fig.l] is a schematic side view of an installation according to the invention;

[0024] [Fig.2] is a schematic side view of another embodiment of an installation according to the invention;

[0025] [Fig. 3] is a schematic side view of yet another embodiment of an installation according to the invention; and

[0026] [Fig.4] is a schematic side view of yet another embodiment of an installation according to the invention.

[0027] In [Fig.l], a needling installation comprises a board 1, from a lower face of which protrude needles 2 arranged in a field of needles which is conventionally produced in a so-called random or quasi-random pattern, the definition of random or quasi-random being well known in the field.

[0028] A vertical column 3 is integral with the needle board and transmits to the latter a back and forth movement which is imparted to it by a connecting rod and crank system (not shown in the figures), the driving of the column 3 being carried out in the figure so as to have a vertical back and forth movement. However, a different drive system could be provided, in particular ensuring that the needles have a movement following an elliptical trajectory, for example by providing additional drive means in a transverse direction also giving the needles a transverse displacement component to thus produce an elliptical trajectory of the needles.

[0029] A web 5 or a sheet of fibers, in particular non-woven, moves in a horizontal direction, called the feed direction, or MD (Machine Direction) opposite the needles.

[0030] Support means, in particular in the form of a support table 6, support the veil or the tablecloth during its movement.

[0031] A stripping plate 8, for example in the form of a sheet, pierced with through holes 9 in a pattern corresponding to that of the needles, is arranged between the needle board 1 and the web or sheet of fibers.

[0032] An accelerometer sensor 9 is arranged integral with the plate 8 and makes it possible to measure the acceleration of the plate 8 forming a stripper in order to thus determine the vibrations and / or deformations undergone by this plate.

[0033] This accelerometer 9 is connected to an electronic control system 10 which makes it possible to display in particular the measurements taken by the accelerometer 9.

[0034] Furthermore, the electronic control system 10 comprises storage means capable of storing the measurements of the accelerometer 9, in particular when no dust is present between the needles on the underside of the board. The electronic control system 10 further comprises comparison means capable of comparing the measurements of the sensor 9 over time and so-called reference measurements corresponding to the measurement carried out by the sensor when no dust is present between the needles on the underside of the board. Thus, by measuring the deformations and / or vibrations of the stripper plate, the accelerometer allows the user to monitor the thickness of the layer of fiber dust that has accumulated on the board between the needles and thus know when this thickness becomes too great to the point of threatening the installation with a long-term blockage due to the breakage of some of its components.

[0035] The control system 10 may further comprise alert means capable of issuing an alert, for example audible, visual or similar, to the user when the difference obtained from the comparison means varies, in particular when it exceeds a threshold determined in advance.

[0036] Following this alert, the user can intervene on the needle board to clean it, thus preventing a jam from causing the breakage of components of the machine, which is likely to result in a recovery time for the line to be restarted which is much longer than the time of a stoppage necessary simply to get rid of the fiber dust.

[0037] Means for removing the clumps of fiber dust may be provided, for example in the form of a blower 11 arranged to send a jet of air between the needles.

[0038] These elimination means can be activated by the user when an alert is issued. It is also possible to provide that the control system 10 triggers the elimination means when the difference value from the comparison means varies, in particular exceeds a threshold value set in advance.

[0039] In [Fig. 2], another embodiment according to the invention is shown, in which means for fixing the stripper plate 8 in the form of rods and / or bearings 12 are connected to strain gauges 13 which measure the forces applied at these fixing points of the stripper plate.

[0040] Following the same principle as in the embodiment of [Fig. 1], knowing that these two monitoring devices can also be combined to form a third embodiment, the strain gauges, initially, measure the force applied when there is no dust on the lower face of the board 1, then the force applied over time, and send their measurement to an electronic control system which performs on these measurements the same processing as that performed by the system 10 on the measurements made by the accelerometer in the first embodiment. In particular, it is possible to provide, in this embodiment, comparison means, alert means and / or means for eliminating fiber dust as in the first embodiment.

[0041] According to the invention, embodiments have been described in which strain gauges and / or an accelerometer are used to determine the deformations and / or vibrations of the stripper plate.

[0042] However, of course, without departing from the scope of the invention, other systems could be used, in particular an electronic camera, a laser meter or any other means of monitoring the thickness of the layer of fiber dust which accumulates on the board between the needles. It is also possible to measure with an electronic camera, a laser meter or the like, the vibrations and / or deformations of the plate, and thus carry out monitoring of the quantity of fiber dust clumps, in particular the corresponding thickness.

[0043] Thus, in [Fig. 3], an embodiment is shown in which a camera 15 records the vibrations and / or deformations of the plate 8 and sends them to the system 10, which, depending on the recorded values, and in particular their variation beyond a threshold value determined in advance, triggers an alert and / or triggers a procedure either manually for eliminating the accumulated dust, in particular by briefly stopping the line, or automatically by actuating means for eliminating the dust clumps.

[0044] As for the embodiment shown in [Fig.4], a camera 16 records the thickness of the layer of dust which accumulates between the needles on the lower face of the board and sends this information to the system 10, which, in the same way as in the other embodiments, when the value of the thickness varies beyond a threshold value, triggers either a manual procedure for eliminating the accumulated dust, in particular by briefly stopping the line, or an automatic procedure by actuating dust elimination means.

Claims

Claims

1. A needling machine installation comprising a needle board (1) comprising a field of needles and means (3) for driving the needles in a back-and-forth movement, in particular in the vertical direction, so that the needles, in one direction of movement, penetrate a web (5) or a sheet of fibers, in particular non-woven, to pass through it in a transverse direction, in particular perpendicular, to the direction in which the web or sheet of fibers moves in front of the needles, then in a second direction of movement, fiber dust emerges from the sheet or sheet of fibers, fiber dust accumulating on the board between the needles, and the installation further comprising a plate (8) forming a stripper which is pierced with a field of through holes and which is crossed by the needles before they penetrate the web or sheet of fibers, characterized in that means (9; 13; 15;16) monitoring of fibre dust accumulating on the board between the needles and alert means capable of giving an alert when the quantity of accumulated fibre dust monitored exceeds a threshold value determined in advance.;

2. Installation according to claim 1, characterized in that the means (9; 13; 15; 16) for monitoring fiber dust comprise means for monitoring vibrations and / or deformations of the plate (8) forming a stripper.

3. Installation according to claim 2, characterized in that the means for monitoring the vibrations and / or deformations of the plate (8) forming a stripper comprise an accelerometer sensor (9).

4. Installation according to claim 2 or 3, characterized in that the means for monitoring the vibrations and / or deformations of the plate (8) forming a stripper comprise means (13) for monitoring the stresses exerted on the points (12) of fixing and / or support of the plate forming a stripper.

5. Installation according to one of the preceding claims, characterized in that the alert means give the alert when the difference between the vibrations and / or deformations monitored over time and the vibrations and / or deformations when empty exceed a threshold value determined in advance.

6. Installation according to one of the preceding claims, characterized in that means (11) are provided for removing fiber dust accumulated between the needles.

7. Installation according to one of the preceding claims, characterized in that control means (10) are provided, in particular electronic, which actuate the warning means and / or the means for eliminating the fiber clumps when it is detected that the quantity of accumulated fiber dust exceeds a threshold value determined in advance, in particular when a variation in the vibrations and / or deformations of the stripper plate is detected, in particular when they exceed a threshold value.

8. Installation according to one of the preceding claims, characterized in that the movement of the needles takes place along a rectilinear trajectory.

9. Installation according to one of claims 1 to 7, characterized in that the movement of the needles takes place along an elliptical trajectory.

10. Method for operating a needling machine installation comprising a needle board (1) comprising a needle field and means (3) for driving the needles in a back and forth movement, in particular in the vertical direction, so that the needles, in one direction of movement, penetrate into a web (5) or a sheet of fibers, in particular non-woven, to pass through it in a transverse direction, in particular perpendicular, to the direction in which the web or the sheet of fibers moves in front of the needles, then in a second direction of movement, fiber dust accumulating on the board between the needles emerges from the sheet or the sheet of fibers, in which: - the fiber dust accumulating on the board between the needles is monitored, and - when the quantity of fiber dust monitored exceeds a threshold value,means (11) are used to eliminate the fiber dust accumulated on the board.

Images