JP3142094B2 - Nozzle plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nozzle plate for entangling fibers by applying a fluid flow to a fiber web.

[0002]

2. Description of the Related Art Conventionally, there has been known an apparatus which obtains a fiber sheet by entanglement of fibers by applying a water flow to a fiber web. However, a water flow is applied while moving the fiber web by a conveyor. Vertical streaks due to the water flow were conspicuous in the flow direction, and a fiber sheet favorable in appearance could not be obtained.

[0003] For this reason, various means have been taken, such as operating the water flow while oscillating it, or applying two or more rows of water flow in a direction perpendicular to the flow direction of the fiber web. A fiber sheet that has been sufficiently eliminated has not been obtained.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to obtain a fiber sheet in which vertical streaks in the flow direction of a conveyor are inconspicuous.

[0005]

According to the present invention, there is provided a horizontally long fluid flow entanglement nozzle plate having a plurality of fluid ejection holes, and a trajectory of a fluid ejected from an arbitrary fluid ejection hole.
The locus L _A1 projected perpendicular plane A with respect to the long axis of the plate, does not coincide with the locus L _A1, the trajectory projected onto the plane A L _{A2 ···} L _Am (m is a natural number of 2 or more) , And an arbitrary trajectory L _A1 and an arbitrary trajectory L _A2.
L _Am intersects with (m-1) or less points C _A1... C _{A (m-1)} , and the point C _A1 is projected on a plane B perpendicular to the short axis of the plate. through the point C _B, the long axis parallel to the straight line S of the plate, the locus L _B1 to the trajectory of the fluid is projected onto the plane B ejected from the fluid ejection _holes, L _{B2 ···} L _Bn (n is a natural number) and intersection C _S1, C _{S2 ···} C _Sn of a nozzle plate with more than 25 points / cm.

[0006] If the fluid ejection holes are arranged in two or more rows, particularly in a staggered manner, a fiber sheet with less noticeable vertical streaks can be obtained.

[0007]

According to the nozzle plate of the present invention, the trajectory L _A1 of the trajectory of the fluid ejected from an arbitrary fluid ejection hole projected on a plane A perpendicular to the long axis of the plate does not coincide with the trajectory L _A1 . L _A2... L _Am (m is a natural number of 2 or more) projected onto the plane A, and has a fluid ejection hole, and an arbitrary trajectory L
Minor axis of _A1 and any locus L _{A2 ···} L _Am A (m-1) pieces are intersected in the following points _{C A1 · · · C A (} m-1), moreover the plates point C _A1 through C _B points projected onto a plane perpendicular B relative to, and parallel to the straight line S and the long axis of the plate, the locus L _B1 in which the trajectory of the fluid ejected from fluid ejection hole is projected on a plane _B,
C _S1, C _S2... C _{Sn with} L _B2... L _Bn (n is a natural number)
Is 25 points / cm or more, the density of the action of the fluid flow ejected from the nozzle plate of the present invention is high, and there is no time difference, so that the fiber sheet is uniformly entangled over the entire fiber web and has no noticeable vertical streaks. Can be obtained.

[0008] The fluid injection holes of the nozzle plate of the present invention may be arranged at random or in two or more rows. Although not particularly limited, the latter is easier to design. It is.

When the fluid injection holes are arranged in two or more rows as in the latter case, it is preferable to arrange them, for example, as shown in FIGS. 1 (a) to 1 (c). That is, in the case of two rows as shown in FIG. 1 (a), the second row of fluid injection holes is located between the adjacent first row of fluid injection holes, preferably 1 in the short axis direction of the nozzle plate. If the fluid injection holes are arranged in a zigzag manner at an intermediate position between adjacent fluid ejection holes, even if the fluid flows are close to each other over the entire fibrous web, it is easy to uniformly perform the entanglement processing without intersecting. Further, as shown in FIGS. 1B and 1C, when the fluid ejection holes are in three rows, the fluid ejection holes in the second row are adjacent to the fluid ejection holes in the first row in the short axis direction of the nozzle plate. It is preferable that the fluid ejection holes in the third row are arranged so as not to overlap between the holes, and the fluid ejection holes in the third row are arranged so as not to overlap between the adjacent fluid ejection holes in the second row. In this case, if the fibers are arranged in a staggered manner between adjacent rows, it is easy to perform the entanglement process uniformly without the fluid flows intersecting over the entire fiber web. Further, as shown in FIG. 1 (c), the third row of fluid ejection holes and the first row of fluid ejection holes may be located at overlapping positions, but the vertical lines are not overlapped so that the vertical streaks are less noticeable. 1 (b)). In addition,
Although not shown, it is preferable that the same relationship as described above is satisfied even when the fluid ejection holes are arranged in four or more rows.

In the present invention, the long axis refers to a straight line passing through the center of gravity of the nozzle plate and parallel to the long side of the nozzle plate, and the short axis refers to a plane parallel to one surface of the nozzle plate including the long axis. A straight line that passes through the center of gravity of the nozzle plate and is perpendicular to the long axis.

As described above, when the fluid ejection holes are arranged in a row, the pitch of the fluid ejection holes in the same row is preferably set to 24 to 10 holes / cm. This pitch is 2
When the length is shorter than 4 holes / cm, adjacent fluid flows easily interfere with each other and it is difficult to uniformly entangle the fluid flows. When the pitch is longer than 10 holes / cm, the vertical streaks tend to be conspicuous. More preferably, it is 20 to 15 holes / cm.

The diameter of the fluid injection holes may be different for each fluid injection hole. However, when the fluid injection holes are arranged in a row, the entanglement effect by the fluid flow in the same row is the same. In order to operate, it is more preferable to make the diameters of the fluid ejection holes in the same row the same. If the diameter of the fluid injection hole is smaller than 0.05 mm, the energy of the fluid flow to be injected is small, so that the confounding process cannot be performed efficiently. Conversely, if the diameter is larger than 0.2 mm, the fibers are hardly entangled. Therefore, 0.05 to 0.2 mm is preferable, and more preferably,
It is 0.07 to 0.15 mm.

Further, when the distance between the rows of the fluid injection holes is less than 0.5 mm, the fluid flows in adjacent rows are likely to interfere with each other. Conversely, when the distance exceeds 2 mm, the angle of incidence of the fluid flow on the fiber web becomes large. 0.5mm ~
It is preferably 2 mm, more preferably 0.5 to 1 mm
It is. The distance between the rows of the fluid injection holes indicates the distance between a straight line passing through the center of the front row of fluid injection holes and a straight line passing through the center of the rear row of the fluid injection holes.

The nozzle plate of the present invention has a plurality of fluid ejection holes as described above, and the trajectory of the fluid ejected from an arbitrary fluid ejection hole of the nozzle plate is defined with respect to the long axis of the plate. A locus L _A1 projected on a vertical plane A,
The locus L projected on the plane A, which does not coincide with the locus L _{A1
A2 ···} L _Am (m is a natural number of 2 or more) having a fluid injection hole with, and is an arbitrary locus L _A1 and any locus _{L A2 ··· L Am (m-} 1) or less Point C _A1... C _{A (m-1)} intersects, and passes through point C _B which projects point C _A1 on a plane B perpendicular to the short axis of the plate, and is parallel to the long axis of the plate and the straight line S such intersection C _S1 of the locus obtained by projecting the locus of the fluid ejected from fluid ejection hole on a plane _{B L B1, L B2 ··· L} Bn (n is a natural _number), C _{S2 ···} C _Sn Is 25 points / cm or more, the density at which the fluid flow acts is high, and the fiber web can be uniformly entangled.

[0015] That is, the trajectory of the fluid expelled out of any fluid injection hole of the nozzle plate, the locus L _A1 projected perpendicular plane A with respect to the long axis of the plate, does not coincide with the locus L _A1 , L _A2... L _Am (m
The 2 or more has a fluid injection hole with a natural number), and any locus L _A1 and any locus L _{A2 · · ·} The L _Am (m-1) or fewer points C _{A1 ···} C _{A The} intersection at _(m-1) means that the trajectory L _A1... exemplifies the case where the number of intersections in FIGS. 2A and 2B and FIGS. 3A and 3B is one. _The angles formed _by L _Am and the nozzle plate are not all right angles, and at least one has a fluid ejection hole having an angle that is not a right angle, and (m−1) or less points CA _1... It means that they meet at C _{A (m-1)} . Note that points C _A1... C
If the nozzle plate is installed such that one point of _{A (m-1)} coincides with the upper surface, middle, or lower surface of the fiber web, the fiber web can be uniformly entangled without a time difference. It is. 2 (a), 2 (b) and 3
In the case of (a) and (b), the nozzle plate may be set so that the point C _A1 coincides with the upper surface, the middle, or the lower surface of the fiber web.

The smaller angle between the locus L _A1... L _{Am on} the plane A and the nozzle plate is 70 to 90.
゜ is preferred. When the angle is less than 70 °, a force for cutting the fiber is applied rather than tangling the fiber web. More preferably, it is 80 to 90 °.

Furthermore, in the present invention, as shown in FIG. 4, the straight line S and the locus L _B1, L _{B2 ···} L intersection between _{Bn C S1, C S2 ··· C} Sn
Must be 25 points / cm or more. This can not be obtained when the fluid injection holes are arranged in a line, and can act on the fiber web at a density of 25 points / cm or more, so that the fibers can be entangled more densely and consequently, the vertical streaks become conspicuous. It became possible to obtain a fiber sheet without. In the present invention, the trajectory of the fluid refers to the center line of the trajectory of the fluid.

The locus L _{A1 on the} plane A and the arbitrary locus L _A2... L _Am are (m−1) or less points C _A1.
Intersection at _{A (m-1)} , intersection points C _S1, C _S2... C _{Sn of} plane B are 25
Even if it is more than the point / cm, the ejected fluid flows interfere with each other before acting on the fiber web, and if the force acting on the fiber web is attenuated, they cannot be uniformly entangled. Preferably has a fluid ejection hole that does not interfere with the fluid ejection. In this case, as described above, when the fluid ejection holes are arranged in two or more rows, particularly, in a staggered manner, it is easy to design the fluid ejection holes so that the fluid flows do not interfere with each other.

Such a nozzle plate 1 of the present invention is installed above a conveyor for transporting the fiber web 2, ejects a fluid flow, and entangles the fiber web 2 to obtain a fiber sheet 3. This nozzle plate 1 has one of the points C _A1... C _{A (m-1)} of the nozzle plate, as shown in FIG.
In the case of (b) and FIGS. 3 (a) and (b), if the point C _A1 is set so as to coincide with the upper surface, the middle, or the lower surface of the fiber web 2, there is no time difference and the fibers can be entangled densely.

As shown in FIGS. 5A and 5B,
The nozzle plate 1 can be arranged so that its major axis is perpendicular to the flow direction of the fiber web 2, or can be arranged obliquely. In the former case, there is no time difference in the width direction of the fiber web 2, so that the fibers can be entangled uniformly. In the latter case, since the fibers are arranged obliquely with respect to the fiber web 2, the fluid flow Are characterized by the fact that the spacing between them is shorter and can be densely entangled.

Hereinafter, embodiments of the nozzle plate of the present invention will be described, but the present invention is not limited to these embodiments.

[0022]

【Example】

(Example) A fiber web having a basis weight of 60 g / m ² obtained by carding a polyester fiber having a fineness of 1.5 denier and a fiber length of 51 mm was perpendicular to the flow direction of the fiber web at a point C _{A1 on a} plane A. Was sprayed from a nozzle plate as described below, which was arranged so as to intersect at the upper surface of the fiber web, to entangle the fibers to obtain a fiber sheet. In this fiber sheet, the vertical streaks due to the water flow were not noticeable, and the surface condition was uniform.

(1) Fluid ejection holes are arranged in two rows in a staggered manner. (2) The pitch of the fluid injection holes in each row is 15 holes / cm. (3) The diameter of the fluid injection holes is 0.15 m for both the first and second rows.
m. (4) The distance between the rows of the fluid injection holes is 0.7 mm. (5) The intersections C _S1, C _S2... C _Sn are 30 points / cm. (6) As shown in FIG. 2 (a), the angle between the fluid injection holes and the nozzle plate in the plane A is 89.2.
2 ゜. (7) in the plane B, the locus L _B1, L _{B2 ···} L _Bn linearly S
Are all at right angles. (8) The discharge pressure of the water flow is 10 MPa.

(Comparative Example 1) A fiber web obtained in the same manner as in the example was sprayed with water from a nozzle plate as described below, which was arranged at right angles to the flow direction of the fiber web.
The fibers were entangled to obtain a fiber sheet. This fiber sheet had a surface where vertical streaks due to water flow were conspicuous.

(1) The fluid injection holes are arranged in a line. (2) The pitch of the fluid injection holes is 20 holes / cm. (3) The diameter of the fluid injection hole is 0.15 mm. (4) The angle between the fluid injection holes and the nozzle plate on the plane A is 90 °. (5) in the plane B, the locus L _B1, L _{B2 ···} L _Bn linearly S
Are all at right angles. (6) The discharge pressure of the water flow is 10 MPa.

(Comparative Example 2) A fiber web obtained in the same manner as in the example was sprayed with water from a nozzle plate as described below, which was arranged at right angles to the flow direction of the fiber web.
The fibers were entangled to obtain a fiber sheet. This fiber sheet had vertical stripes of light and shade due to the water flow, and the surface condition was not uniform.

(1) Fluid ejection holes are arranged in two rows in a staggered manner. (2) The pitch of the fluid injection holes in each row is 15 holes / cm. (3) The diameter of the fluid injection holes is 0.15 m for both the first and second rows.
m. (4) The distance between the rows of the fluid injection holes is 0.7 mm. (5) The intersections C _S1, C _S2... C _Sn are 30 points / cm. (6) The angle between the fluid injection holes and the nozzle plate on the plane A is 90 °. (7) in the plane B, the locus L _B1, L _{B2 ···} L _Bn linearly S
Are all at right angles. (8) The discharge pressure of the water flow is 10 MPa.

[0028]

According to the present invention, since the density of the action of the fluid flow ejected from the nozzle plate of the present invention is high and there is no time lag, it is possible to obtain a fiber sheet which is uniformly entangled over the entire fiber web and has less noticeable vertical streaks. it can.

[Brief description of the drawings]

FIG. 1A is an example of a plan view of a nozzle plate. FIG. 1B is an example of a plan view of a nozzle plate. FIG.

2A is an example of a diagram illustrating a trajectory projected on a plane A. FIG. 2B is an example of a diagram illustrating a trajectory projected on a plane A.

3A is an example of a diagram illustrating a trajectory projected on a plane A. FIG. 3B is an example of a diagram illustrating a trajectory projected on a plane A.

FIG. 4 is an example of a diagram showing a trajectory projected on a plane B;

FIG. 5A is an example of a plan view in a state where a nozzle plate is installed. FIG. 5B is an example of a plan view in a state where a nozzle plate is installed.

[Explanation of symbols]

1 nozzle plate 2 the web 3 the fibrous sheet A plane A B plane B C _{A1 ···} C _Am locus L _A1 and the locus L _{A2 ···} L _Am and point intersecting C _B C point obtained by projecting the plane B an _A C _S1, C _{S2 ···} C _Sn locus L _B1, L _{B2 ···} L _Bn and the straight line S locus projected in the intersection L _A1 plane a of the L _{A2 ···} L _Am locus L _A1 plane a not match the locus L _B1 projected _onto, L _{B2 ···} L _Bn through the plane trajectory point S C _B projected onto B, straight line parallel to the long axis of the nozzle plate

Claims (3)

(57) [Claims] 1. In a horizontally long fluid flow entanglement nozzle plate having a plurality of fluid ejection holes, a trajectory of a fluid ejected from an arbitrary fluid ejection hole is set on a plane A perpendicular to a long axis of the plate. the locus L _A1 projected, does not coincide with the locus L _A1, the locus L _{A2 · ·} L _Am projected onto the plane a (m is a natural number of 2 or more) having a fluid injection hole with, and any locus L _A1 and an arbitrary trajectory L _A2... L _Am intersect at (m-1) or less points C _A1... C _{A (m-1)} , and the point C _{A1 is positioned} with respect to the short axis of the plate. Trajectories L _{B1 and} L _B that pass through a point CB projected on a vertical plane B and are parallel to the long axis of the plate and a trajectory of the fluid ejected from the fluid ejection holes onto the plane B.
A nozzle plate characterized in that the number of intersections C _S1, C _S2... C _Sn with _B2... L _Bn (n is a natural number) is 25 points / cm or more. 2. The nozzle plate according to claim 1, wherein the fluid ejection holes are arranged in two or more rows. 3. The nozzle plate according to claim 2, wherein the fluid ejection holes are arranged in a staggered manner.