JP6008703B2 - Stretchable composite sheet manufacturing apparatus and manufacturing method - Google Patents

Description

  The present invention relates to a technique for manufacturing a stretchable composite sheet in which an elastic member is sandwiched between two webs.

  Such manufacturing techniques are disclosed in the following Patent Documents 1 and 2.

In the invention of JP2002-143218 A1, by changing the peripheral speed of the speed adjusting roll brought into contact with the elastic member being continuously conveyed, the conveying speed of the elastic member is changed and the elastic member is joined to the web. Change the elongation rate. Thereby, the composite sheet from which the expansion / contraction rate of an elastic composite sheet differs intermittently is obtained.

In the invention of JP2003-38565 A1, the elastic member is swung with respect to the flow direction of the conveyed web, and the elastic member is attached along a predetermined locus by niping the web and the elastic member.

JP2002-143218 A1 (abstract) JP2003-38565 A1 (abstract)

  However, in the method for attaching the elastic member disclosed in Patent Document 2, when the expansion rate of the elastic member is changed as in the invention disclosed in Patent Document 1, the speed adjustment roll requires a certain radius. . Therefore, the portion for controlling the elongation rate cannot be arranged near the nip portion, and the distance between the portion for controlling the elongation rate and the nip portion becomes long. Therefore, the elongation rate of the elastic member to be attached cannot be accurately controlled.

  Accordingly, an object of the present invention is to provide an apparatus and a method for manufacturing a stretchable composite sheet capable of realizing a desired change in the elongation rate of an elastic member.

The apparatus of the present invention includes a pair of nip rolls that sandwich two webs at the nip portion and sandwich an elastic member between the two webs.
A first arm that moves along the axial direction of the nip roll and guides the elastic member toward the nip portion;
A second arm that supplies the elastic member toward the first arm and moves along the axial direction to change an expansion ratio of the elastic member supplied to the first arm.

On the other hand, the method of the present invention includes a step of deriving the elastic member from a first arm moving along the axial direction of the pair of nip rolls toward a nip portion where the pair of nip rolls approach each other;
Changing the expansion ratio of the elastic member supplied to the first arm by supplying the elastic member from the second arm moving along the axial direction toward the first arm;
And sandwiching the two webs at the nip portion, and sandwiching the elastic member led out from the first arm between the two webs.

According to the present invention, the elastic member is supplied from the second arm to the first arm that leads the elastic member toward the nip portion, and the second arm is moved in the axial direction. Therefore, the expansion rate (tension) of the elastic member between the second arm and the first arm changes.
On the other hand, unlike the roll, the first and second arms are compact and can enter or approach a delta-shaped space formed between nip rolls. Therefore, the distance from the lead-out portion of the elastic member of the first arm to the nip portion can be reduced, and as a result, the change in the expansion rate of the elastic member can be a desired accurate change.

In the present invention, the elastic member includes a rubber thread and hot melt resin as well as an elastic tape, and refers to a member that extends greatly and can shrink to the original length or a length close to the original length. .
Further, the elongation rate means the ratio of the length of the elastic member when a load (tensile force) is applied to the length of the elastic member when there is no load.

FIG. 1 is a partially sectional side view of a manufacturing apparatus showing an embodiment of the present invention. FIG. 2 is a plan view showing the tension adjusting mechanism. FIG. 3 is a conceptual front view of the same.

Preferably, an endless first belt to which the first arm is attached, a pair of first pulleys that rotate the first belt, and a first that rotationally drives at least one of the pair of first pulleys. And a servo motor.
In this case, the mechanism for moving and controlling the first arm is compact.

More preferably, an endless second belt to which the second arm is attached, a pair of second pulleys for rotating the second belt, and at least one of the pair of second pulleys for rotational driving. And 2 servo motors.
In this case, the mechanism for controlling the movement of the second arm is compact.

More preferably, a delivery mechanism for delivering the elastic member toward the second arm, and a first mechanism attached to the first arm and configured to turn the elastic member supplied from the second arm in a direction toward the nip portion. And a second moving pulley attached to the second arm and configured to turn the elastic member fed from the feeding mechanism toward the first arm.
A pulley (pulley) is used for conveying (supplying) the elastic member, the elastic member is smoothly conveyed and the elongation rate is easily controlled, and the first and second arms are further compacted. It is easy to place both arms close to the nip.

Preferably, the expansion rate of the elastic member between the first arm and the second arm is controlled by controlling the rotation of the second servo motor in accordance with the position of the first arm in the axial direction. A controller for controlling is further provided.
In this case, the extension rate can be controlled according to the position of the first arm in the axial direction.

Preferably, a feeding mechanism is further provided that feeds the elastic member at a constant speed toward the second arm.
In this case, the elongation rate can be accurately controlled.

Preferably, the apparatus further includes a delivery mechanism that delivers the elastic member toward the second arm, and a controller that changes a speed of the elastic member delivered from the delivery mechanism at a predetermined period.
In this case, it is easy to change the expansion rate greatly.

More preferably, when the elongation rate increases, control is performed such that the speed of the elastic member sent out from the delivery mechanism decreases. On the other hand, when the elongation rate decreases, the speed of the elastic member delivered from the delivery mechanism. Is controlled to be large.
In this case, it is easy to change the expansion rate further.

The invention will be more clearly understood from the following description of preferred embodiments with reference to the accompanying documents. However, the examples and figures are for illustration and description only and should not be used to define the scope of the present invention. The scope of the present invention is defined only by the claims. In the accompanying drawings, the same part numbers in a plurality of drawings indicate the same or corresponding parts.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
1 to 3 show an apparatus for producing a stretchable composite sheet FW in which an elastic member F is sandwiched between two webs W. FIG.

In FIG. 1, the pair of nip rolls 1R sandwiches two webs W at a nip portion 1N approaching each other, and sandwiches an elastic member F between the two webs W. The two webs W, W are, for example, disposable pants or a diaper nonwoven fabric. An adhesive is applied from the applicator 5 to at least one surface of the webs W, W facing each other. The elastic member F is, for example, thread rubber.

As shown in FIG. 3, the manufacturing apparatus includes a lead-out mechanism 1 for leading the rubber thread to the nip portion 1N, a tension adjusting mechanism 2 for changing the elongation ratio (tension) of the rubber thread, and a delivery mechanism 3. With. The derivation mechanism 1 and the tension adjusting mechanism 2 are respectively composed of first and second arms 10 and 20, first and second belts 11 and 21, first and second pulleys 12 and 22, and first and second moving pulleys. 13 and 23 are provided.

The first arm 10 moves along the axial direction S of the nip roll 1R. The first moving pulley 13 is attached to the first arm 10 and turns the elastic member F supplied from the second arm 20 in a direction toward the nip portion 1N and supplies it to the lead-out portion 14. The lead-out portion 14 leads the elastic member F from the first moving pulley 13 toward the nip portion 1N.

The first arm 10 is attached to the endless first belt 11 shown in FIG. The first belt 11 is rotated by a pair of first pulleys 12 and 12. In this example, at least one of the pair of first pulleys 12 is rotationally driven, and a first servo motor M1 shown in FIG. 3 is provided.

Accordingly, when the first servo motor M1 rotates forward and backward, the first pulley 12 and the first belt 11 rotate forward and backward. Accordingly, the first arm 10 moves in the axial direction S, while the nip roll 1R conveys the web W. Therefore, the elastic member F moves on the web W along a predetermined locus indicated by a two-dot chain line on the nip roll 1R. , W are introduced.

The second arm 20 supplies the elastic member F toward the first arm 10 and moves along the axial direction S, so that the expansion rate of the elastic member F supplied to the first arm 10 is increased. To change. As will be described later, the delivery mechanism 3 delivers the elastic member F toward the second arm 20. The second arm 20 includes a second moving pulley 23 that turns the elastic member F fed from the feed mechanism 3 toward the first arm 10.

The second arm 20 is attached to the endless second belt 21 of FIG. The second belt 21 is rotated by a pair of second pulleys 22 and 22. A second servo motor M2 shown in FIG. 3 is provided to rotate and drive at least one of the pair of second pulleys 22 in this example.

Accordingly, when the second servo motor M2 rotates forward and backward, the second pulley 22 and the second belt 21 rotate forward and backward. Along with this, the second arm 20 moves in the axial direction S, and the expansion rate of the elastic member F changes.

As shown in FIG. 1, the first and second arms 10 and 20 are attached to the first and second belts 11 and 21 via sliders 15 and 15, respectively. The sliders 15 and 15 are guided by rails 16 and 16 extending in the axial direction S. Therefore, the arms 10 and 20 are less likely to shake during movement and are less likely to vibrate.

As shown in FIG. 1, the first and second pulleys 12 and 22 are arranged such that the first axis 12s and the second axis 22s intersect each other in the side view of FIG. Note that the first and second axes 12s and 22s in FIG. 1 may be arranged symmetrically with each other in the side view of FIG. 1 around the common tangent line 1L of the pair of nip rolls 1R.

As shown in FIG. 2, the second belt 21 is longer in circumference than the first belt 11, and a part of the first belt 11 is disposed in the second belt 21. Thereby, as shown in FIG. 2, the first and second belts 11 and 21 and the first and second pulleys 12 and 22 having the same shape and the same size can be arranged in a compact manner.

3 includes a feed drum 30 that feeds the wound elastic member F, a third servo motor M3 that rotationally drives the feed drum 30, and a bracket 31 that is fixed to the frame 6 (FIG. 1). And a third pulley 33 rotatably attached to the bracket 31.

The first to third servo motors M1 to M3 in FIG.
The controller 4 controls the rotation of the first servo motor M1 so that the elastic member F is introduced between the webs W and W (FIG. 1) along a predetermined trajectory. The position in the axial direction S of 10 and the speed in the axial direction S of the first arm 10 at the position are controlled.

The controller 4 controls the rotation of the second servo motor M2 in accordance with the position of the first arm 10 in the axial direction S, thereby moving the second arm 20 in the axial direction S, so that the first arm 10 And the extension ratio of the elastic member F between the second arm 20 and the second arm 20 is controlled. That is, the controller 4 controls the expansion ratio by controlling the relative position of the second arm 20 in the axial direction S with respect to the first arm 10. When the distance between the first arm 10 and the second arm 20 is large, the expansion / contraction ratio increases, and when the distance between the first arm 10 and the second arm 20 is small, the expansion / contraction ratio decreases.

For the sake of drawing, the first moving pulley 13, the second moving pulley 23, and the third pulley 33 are illustrated at positions separated from each other in the radial direction orthogonal to the axial direction S. However, they are close to each other in the radial direction. It is preferable. This is because the elongation rate is accurately controlled and the apparatus becomes compact.

The third servo motor M3 may rotate at a constant speed, and the elastic member F wound around the feed drum 30 may be sent to the second moving pulley 23 via the third pulley 33 at a constant speed.

On the other hand, the third servomotor M3 may rotate the feed drum 30 while shifting the feed drum 30 at a predetermined cycle according to the position of the first arm 10 in the axial direction S. For example, when the controller 4 controls the rotation of the feed drum 30 via the third servo motor M3 and increases the expansion rate, the speed of the elastic member F fed from the feed mechanism 3 is reduced. On the other hand, when decreasing the expansion ratio, the elastic member F fed from the feed mechanism 3 may be controlled so as to increase in speed.

That is, when the distance between the first arm 10 and the second arm 20 is increased, the speed of the elastic member F fed from the feed drum 30 is decreased. On the other hand, when the distance between the first arm 10 and the second arm 20 is decreased, the speed of the elastic member F fed from the feed drum 30 is increased.

Note that a sensor 7 such as a proximity switch shown in FIG. 1 may be provided to detect the reference positions of the first arm 10 and the second arm 20.

Below, the manufacturing method of the elastic composite sheet FW is demonstrated.
In FIG. 1, an adhesive is applied to the pair of webs W, W from the applicator 5, and the webs W, W are bonded together at the nip portion 1N of the pair of nip rolls 1R. At this time, the elastic member F is sandwiched between the webs W and W, and the stretchable composite sheet FW is generated.

In FIG. 3, the elastic member F is fed out from the feed drum 30 by the rotation of the third servo motor M <b> 3 and is supplied to the lead-out unit 14 while being turned in the third pulley 33, the second moving pulley 23, and the first moving pulley 13. In the nip portion 1N, the lead-out portion 14 is supplied and sandwiched between the webs W and W.

When the elastic member F is led out from the lead-out part 14, the first arm 10 moves in the axial direction S together with the first belt 11 by forward and reverse rotation of the first servo motor M1, while the nip roll 1R rotates. The elastic member F is sandwiched between the webs W along a trajectory having a predetermined period.

On the other hand, the controller 4 controls the rotation of the second servo motor M <b> 2 according to the position of the first arm 10 in the axial direction S, and moves the second arm 20 together with the second belt 21 in the axial direction S. The elastic member F is supplied from the second arm 20 moving along the axial direction S toward the first arm 10. By the movement of the second arm 20, the expansion ratio of the elastic member F supplied to the first arm 10 is changed (controlled).

In this way, the elastic composite sheet FW in which the elastic member F is disposed between the two webs W and W along a predetermined locus is generated. The stretchable composite sheet FW has an elongation rate (tension) corresponding to the part in the predetermined locus. Therefore, the worn article can be easily fitted to the wearer, or has an advantage that it is difficult to shift.

As described above, the preferred embodiments have been described with reference to the drawings. However, those skilled in the art will readily understand various changes and modifications within the obvious scope by looking at the present specification.
For example, before the elastic member F is sandwiched between the two webs W, a hole for passing the leg may be formed. An absorbent body may be disposed on the stretchable composite sheet FW laminated integrally.
Further, a curved fit gather as shown in JP-A-7-299094 may be formed together with the leg gather.
Further, the first and second arms 10 and 20 do not need to move completely parallel to the axial direction S, and may be slightly inclined.
Accordingly, such changes and modifications are to be construed as within the scope of the present invention as defined by the claims.

The present invention can be applied to the placement of elastic members such as disposable diapers, pants, or feminine sanitary products.

1N: Nip part 1R: Nip roll 1L: Common tangent 1: Deriving mechanism 10: First arm 11: First belt 12: First pulley 12s: First axis 13: First moving pulley 14: Deriving part 15: Slider 16: Rail 2: Tension adjusting mechanism 20: Second arm 21: Second belt 22: Second pulley
22s: second axis 23: second moving pulley 3: feeding mechanism 30: feeding drum 31: bracket 33: third pulley 4: controller 5: coating machine 6: frame 7: sensor F: elastic member
FW: Stretchable composite sheet M1 to M3: First to third servo motors S: Axial direction W: Web

Claims (9)

An apparatus for producing a stretchable composite sheet in which an elastic member is sandwiched between two webs,
In the nip portion, a pair of nip rolls sandwiching two webs and sandwiching an elastic member between the two webs;
A first arm that moves along the axial direction of the nip roll and guides the elastic member toward the nip portion;
A second arm that supplies the elastic member toward the first arm and moves along the axial direction to change an expansion rate of the elastic member supplied to the first arm. In the manufacturing apparatus of Claim 1,
An endless first belt to which the first arm is attached;
A pair of first pulleys for rotating the first belt;
And a first servo motor that rotationally drives at least one of the pair of first pulleys. In the manufacturing apparatus of Claim 2,
An endless second belt to which the second arm is attached;
A pair of second pulleys for rotating the second belt;
And a second servo motor that rotationally drives at least one of the pair of second pulleys. In the manufacturing apparatus of Claim 3,
A delivery mechanism for delivering the elastic member toward the second arm;
A first moving pulley attached to the first arm and turning the elastic member supplied from the second arm in a direction toward the nip portion;
And a second moving pulley attached to the second arm and configured to turn the elastic member fed from the feed mechanism toward the first arm. In the manufacturing apparatus of Claim 3,
A controller that controls the expansion rate of the elastic member between the first arm and the second arm by controlling the rotation of the second servo motor according to the axial position of the first arm. Is further provided. In the manufacturing apparatus of Claim 1,
The apparatus further includes a delivery mechanism that delivers the elastic member at a constant speed toward the second arm. In the manufacturing apparatus of Claim 1,
A delivery mechanism for delivering the elastic member toward the second arm; and a controller for changing a speed of the elastic member delivered from the delivery mechanism at a predetermined cycle. 8. The manufacturing apparatus according to claim 7, wherein the controller includes:
When the expansion rate increases, control is performed so that the speed of the elastic member sent out from the delivery mechanism decreases. On the other hand, when the expansion rate decreases, the speed of the elastic member sent out from the delivery mechanism increases. To control. A method for producing a stretchable composite sheet in which an elastic member is sandwiched between two webs,
Deriving the elastic member from a first arm that moves along the axial direction of the pair of nip rolls toward a nip portion where the pair of nip rolls approach each other;
Changing the expansion rate of the elastic member supplied to the first arm by supplying the elastic member from the second arm moving along the axial direction toward the first arm;
And sandwiching the two webs at the nip portion, and sandwiching the elastic member led out from the first arm between the two webs.

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