JPH06209968A - Installation of waist band of paper diaper - Google Patents

Abstract

PURPOSE:To smoothly install an elastic strip piece forming a waist band in an extension state at the waist part of a paper diaper by spray-coating a hot melt type adhesive on a back sheet which is substantially nonelastic, in the attachment of the waist band. CONSTITUTION:As for a waist band installing device, an elastic band 9 taken out from a roll 8 is applied with a tension by a tension roller 28, etc., at a tension station F. After passing through a slackening station H having a U shaped loop 34 formed, the elastic band 9 passes through between an anvil 35 and a cutting device 36 in a cutting station I, and is cut, and an individual waist band 5 is obtained. In succession, both the edge parts of the waist band 5 are nipping-held by a gripper 39 in an extension station E, and extended. Then, the waist band 5 is attached on a back sheet 1 which turns around an assembly drum 40. At this time, an adhesive is supplied on the back sheet 1, not on the waist band 5, by a spray gun 33.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of attaching a waistband to a disposable diaper.

[0002]

2. Description of the Related Art In disposable diapers, a paper diaper having a waist band attached around the waist is provided on the market in order to prevent leakage of urine before and after. In addition, various proposals have been made to improve fit of the waist band and surely prevent front and rear leakage.

However, when it comes to the mounting method or device, Japanese Patent Application Laid-Open Nos. 60-17102 and 6 are known.
The number is extremely small, such as in Japanese Patent Laid-Open No. 3-219602. this is,
In the case of an elastic band that is attached around the legs, it can be relatively easily done by controlling the speed difference between the delivery rolls because it can be attached by stretching it in the line direction. It is thought that this is affected by the difficulty of mounting by extending in the transverse direction of the line.

In that respect, in the case of the device disclosed in the above-mentioned Japanese Patent Laid-Open No. 63-219602, the work of stretching the waist band in the width direction of the diaper and adhering it can be performed reliably and efficiently, and a high line speed is achieved. It attracts attention as a realizable device.

[0005]

However, in the case of the device disclosed in Japanese Patent Laid-Open No. 63-219602, the elastic band to be the waist band is directly fed to the elastic band in the process of being supplied to the stretching station and the assembling station. Since an adhesive such as hot melt is applied, various problems as described below occur.

(1) When an adhesive is applied to an elastic band such as foamed polyurethane or non-foamed polyurethane, the amount of the adhesive impregnated with the adhesive must be taken into consideration when determining the amount of application. There is a problem that the adhesive for a minute is wasted.

(2) Generally, it is preferable to use a hot melt adhesive as the adhesive. The hot melt adhesive is used by heating it to a temperature higher than a predetermined temperature during application, but when applied to the elastic band, the expansion rate of the elastic band changes due to heat, and the elastic band is applied to the web at a specified length. There is a drawback that it cannot be attached. Moreover, the elastic band may be deteriorated by the hot melt adhesive at high temperature.

(3) The elastic band is very easily twisted. Therefore, if the bead is applied in a twisted state, an adhesive unapplied part is formed, and if it is a product at the assembly station in this state, the desired contraction force for the waist cannot be obtained. In some cases.

Therefore, a main object of the present invention is to solve the above-mentioned problems and to smoothly attach and fix an elastic strip serving as a waist band to a waist portion of a disposable diaper in a stretched state.

[0010]

Means for Solving the Problems The above-mentioned problem is that a continuous elastic band whose elastic band width is the length in the diaper width direction of a waist band adhered to both ends in the longitudinal direction of a paper diaper is provided by a separately installed elastic band roll. In the process of continuously feeding out and supplying to the diaper assembling station, the waist band is sequentially cut to the longitudinal length of the diaper, and both ends of the cut elastic band are held by the holding means so that both holding points are separated during transportation. By doing so, it is conveyed to the assembly station in a state of being stretched in the line width direction, and in the process of supplying the non-elastic, water-impermeable web to the assembly station, the hot-melt adhesive is sprayed on the waist band arrangement part. Then, at the assembly station, the stretched elastic strip is overlapped with the hot melt adhesive application position on the web. It can be solved by adhering Te.

[0011]

In the present invention, when the waist band is adhered, the hot-melt adhesive is directly applied to the elastic band which becomes the waist band, but it is not applied to the substantially inelastic back sheet. Spray application of melt adhesive. Therefore, various problems that have been problems in the past can be solved at once, and the waist band can be smoothly attached and fixed.

[0012]

EXAMPLES The present invention will be described in detail below based on examples. Generally, as shown in FIGS. 1 and 2, a disposable diaper is
For example, a structure in which a backsheet 1 made of a liquid-impermeable material such as a polyethylene film and a topsheet 2 made of a water-permeable material such as a non-woven fabric are wrapped around an absorbent body 3 mainly made of cotton-like pulp. Is the basic structure.

Elastic elastic members 4 and 4 made of rubber or the like are provided along the longitudinal direction on both sides of the disposable diaper. Further, elastic stretchable waist bands 5 are provided along the width direction of the diaper in the partial flap portions at both ends in the longitudinal direction of the diaper where the absorber 3 is not interposed. Since the elastic elastic member 4 is fixed to at least one of the sheets 1 and 2 in a stretched state, it causes the flap portion to contract in the longitudinal direction. Further, since the waist band 5 provided on the waist portion is fixed to at least one of the sheets 1 and 2 in the stretched state, the flap portion is contracted in the width direction. This prevents leakage of urine from around the legs and front and rear leakage.
By the way, as the material of the waist band 5, polyethylene, polyurethane, styrene butadiene, silicone, polyester, vinyl chloride, or foam of neoprene rubber can be used as a material, but from the viewpoint of low cost, polyurethane foam or polyethylene foam is used. Is preferred.
The foamed cell structure is preferably an open cell or compressed open cell structure from the viewpoint of air permeability.

The continuous synthetic sheet N in which the above-mentioned paper diapers are continuously arranged is continuously manufactured in a manufacturing line, and a transverse line C
Individual products are cut along.

An outline of an apparatus for manufacturing the above-mentioned paper diaper will be described with reference to FIGS. 3 and 4. First, the backsheet 1 is a backsheet feeding means which is continuously fed from two backsheet rolls 17, 17. 16 from the 16 to the assembling station 7 and the top sheet 2
Similarly, the two top sheet rolls 15, 15 are continuously conveyed to the assembling station 7 from the top sheet supply means 14 which is successively fed out.

Further, the absorbent body 3 is continuously cut from the continuous belt-shaped absorbent material sheet 11 into a predetermined length by a known cutting means 12 and then continuously assembled by a conveyor 13 at appropriate intervals. It is transported to 7. In each of the diaper constituent materials thus collected in the assembly station 7, the backsheet 1 and the topsheet 2 are adhered to each other with the absorber 3 interposed therebetween, and the waistband 5 will be described in detail later. Waistband attachment device 6
The elastic sheet 4 is attached to the waist of the diaper, and the elastic elastic members 4 and 4 are bonded in the longitudinal direction of the diaper to form a synthetic sheet in which the individual paper diapers shown in FIG. It is conveyed to a station (not shown) where the cutting line C is cut into individual products.

The waist band attaching device 6 comprises a tension station F, a relaxation station H, a cutting station I, a transfer station J, and a stretching station E.

First, in the tension station F, a continuous sheet-like elastic band 9 as a waist band material unwound from the elastic band roll 8 is elastic band 9 by the action of the first guide roller 25, its own weight or a tension spring. A predetermined tension is applied when passing through the tension roller 28 for applying tension to the second guide roller 26. Here, the width of the elastic band 9 is equal to the width of the waist band 5
It is the same as the length of the diaper in the width direction.

Thereafter, the elastic band 9 is attached to the third guide roller 3
After passing through the relaxation station H around the U-shaped loop 34, which has a U-shaped loop 34 in a hanging state, it is sent to the next cutting station I. The third guide roller 32 is rotationally driven by a motor 48 controlled by a transmission 49. The transmission 49 includes a speed sensor 5 for detecting the rotation speed of the anvil 35 of the cutting station I.
The signal from the position sensor 51 at the bottom of the U-shaped loop 34 is captured while the signal from 0 is captured, and the rotation speed of the third guide roller 32 is controlled based on these functions. Therefore, the third guide roller 32 rotates in synchronization with the cutting station I.

On the other hand, the feeding from the elastic band roll 8 is performed by an endless belt 52 driven by a motor 53 controlled by a transmission 54. The control of the feeding speed is based on the signals from the speed sensor 55 arranged on the third guide roller 32 part and the roller position sensor 56 arranged on the tension roller 28 part.
It is controlled based on these functions. Therefore, the feeding speed from the elastic band roll 8 also depends on the third guide roller 3
It is possible to synchronize with the driving speed of No. 2 and to always apply a constant tension to the elastic band 9 by controlling the position of the tension roller 28. As described above, a series of conveyance control up to the cutting station I is performed in synchronization.

In the cutting station I, the anvil 35 and the cutting device 36 have two axes that are parallel to each other and are arranged in contact with each other, and the elastic band 9 passing between them is the longitudinal length of the diaper of the waist band. The waist bands 5 are individually cut into pieces.

Thereafter, the waist band 5 is attached to the conveying drum 3
While being held on the peripheral surface of No. 8, the next drawing station E
Sent to. To hold the waist band 5 on the transport drum 38, as shown in FIG. 7, for example, stepped notches 37 are formed at both ends of the circumferential surface of the transport drum 38, and suction holes 38a communicating with the outer circumferential surface are formed. , 38a ... Is formed and suction is performed from the inside of the drum, so that the waist band 5 can be held on the peripheral surface.

The stretching station E includes a transport drum 38 of the transport station J and a drum 40 of the assembly station 7.
Has a shaft 78 parallel to the rotation axis of the shaft 78. The shaft 78 is axially spaced, and two disk-shaped flanges 79 are fixed in a direction extending in a plane perpendicular to the rotation axis. . Each flange 79 is provided with five grippers 39 at regular intervals in the circumferential direction. In this case, between the flanges 79, 79, the gripper 3
9 and 39 are positioned in the same circumferential direction so as to correspond to each other in a ratio of 1: 1 and the grippers 39 and 39 facing each other form a pair to sandwich both ends of the waist band 5 and extend in the diaper width direction (line width direction). Let

The gripper 39 has a guide rod 8 inserted into a block 80 fixed to a flange 79.
A flange 79 is swingably attached to a support member 80 supported by No. 1 around a shaft 39a as a rotation center. The support member 80 is a guide rod 81.
Is movable in the axial direction, so that the shaft 78
Is movable in the same direction as, and the waist band 5 is stretched by moving the gripper 39 in the direction of the shaft 78. As shown in FIG. 7, the gripping mechanism of the gripper 39 is swingable by a rotary shaft 39a, and in a normal state, the holding force of a spring 83 connected to a part of the support member 80 causes the chain line shown in the figure to move. As shown in FIG.
Are pressed against the tip surface of the support material 80. on the other hand,
A sliding roller 89 is attached to the rear end portion of the gripper 39 so as to come into contact with one circumferential surface (arc-shaped curve 90a) of the cam 90 provided in proximity during the rotational movement of the flange 79. ing. When viewed in cross section as shown in FIG. 6, the shape line of the arc-shaped curve 90a is a shape line which gradually approaches the flange 79, and the roller 89 moved along this shape line. Gripper 39
Automatically rock. This swinging operation causes a gap between the holding portion 84 of the gripper 39 and the support member 80.
Then, during this separation, the sliding roller 89 is disengaged from the cam 90 and returns to the normal state in a state where the waist band 5 inserted synchronously is positioned in the portion.
As shown by the chain line in FIG. 6, the end portion of the waist band 5 is held by the holding portion 84 of the grip 39.

On the other hand, in the slide operation mechanism of the support member 80, as shown in FIGS. 5 and 6, a swingable connecting rod 85 having a rotating shaft 85a is disposed inside the flange 79. The other end of the installation rod 85 is axially supported by the support member 80, and a locking roller 86 provided so as to project from the body of the continuous installation rod 85 is located in the middle of the shafts 78, 78 and on the concentric shaft. It is engaged with a circumferential groove 87 formed on the outer peripheral surface of a cylindrical sleeve 88 that does not rotate. Therefore, as the flange 79 rotates, the connecting rod 85 is guided by the locus of the circumferential groove 87 of the sleeve 88 to swing, and the swinging movement causes the support member 80 to slide. Thus, gripper 3
The waist band 5, whose both end portions are sandwiched by 9, 39, is moved to the assembly drum 40 of the adjacent assembly station J while the support member 80 is moved, so that the gripper 3 is moved.
The waist band 5 is stretched in the line width direction by moving the members 9 and 39 away from each other.

The waist band 5 that has reached the contact position with the assembly drum 40 in the stretched state is sandwiched between the assembly drum 40 and the pressing drum 44 that rotates, and at the same time, the waist band 5 that circulates around the assembly drum 40. It is adhered to the sheet 1 in a stretched state.

At the same time, the rear end roller 8 of the gripper 39 is attached to one circumferential surface of the cam 91 which is disposed in close proximity thereto.
9 comes into contact with the roller 8 according to the shape of the peripheral surface of the cam 91.
By pressing 9 to move and swinging the gripper 39, a gap is created between the holding portion 84 and the support member 80, and the waist band 5 is released from the holding of the gripper 39.

The back sheet 1 and the waist band 5 are adhered to each other by applying the spray gun 33 without applying an adhesive to the elastic band 9 serving as the waist band 5. Applied to. The coating spray gun 33 is adapted to be supplied with the hot-melt adhesive, which is pressure-fed by a hot-melt adhesive pressure-feeding pump (not shown). A control valve that opens and closes according to a command from a control device that sets The adhesive application width of the application spray gun 33 is appropriately selected depending on the width of the waist band 5.

When the waist band 5 in the stretched state is bonded to the back sheet 1 as described above,
While being on the assembly drum 40, the synthetic sheet is guided to a joint portion with the top sheet 2 located at the upper portion, and is bonded with the absorbent body 3 supplied from another line interposed therebetween, and a disposable diaper is continuously provided. Get N. In that state, the synthetic sheet N is cut at the cutting line C position at the next cutting station to be an individual product.

[0030]

As described above in detail, according to the present invention, since the hot melt adhesive is applied to the substantially inelastic web, the hot melt is not impregnated with the hot melt adhesive. The amount of adhesive used can be reduced, and a small amount of adhesive exerts a reliable adhesive force. In addition, various adverse effects of the adhesive on the elastic band can be removed. Further, even if the tension of the elastic band is changed, the coating amount of the hot melt adhesive does not change, and it is possible to always obtain a constant bonding strength. Even if a twist occurs during the supply of the elastic band, the elastic band can be fixed regardless of the twist. Since the elastic band is not impacted when the adhesive is applied, various advantages such as prevention of cutting at the time of application are brought about.

[Brief description of drawings]

FIG. 1 is a perspective view of a continuous sheet of a disposable diaper.

FIG. 2 is a sectional view of a continuous sheet of a disposable diaper.

FIG. 3 is a schematic diagram of a disposable diaper production line.

FIG. 4 is a schematic view of a waist band attaching device.

FIG. 5 is a partial plan view of the waist band attaching device.

FIG. 6 is a detailed view of the grip portion structure of the stretching station.

FIG. 7 is an enlarged detailed view of a grip portion of the stretching station.

[Explanation of symbols]

1 ... Back sheet, 2 ... Top sheet, 3 ... Absorber, 4
... Elastic elastic members, 5 ... Waist band, 6 ... Waist band attaching device, F ... Tension station, H ... Relaxation station, I ... Cutting station, J ... Conveying station, E ... Stretching station

Claims (1)

[Claims] 1. A diaper assembling station in which a continuous elastic band whose elastic band width is the diaper width direction length of a waist band adhered to both longitudinal ends of a paper diaper is continuously fed out from a separately installed elastic band roll. In the process of supplying to the diaper, the waist band is sequentially cut into the length in the longitudinal direction of the diaper, and the both ends of the cut elastic band piece are held by the holding means, and both holding points are separated during conveyance, so that the line width direction is increased. In the process of transporting the stretched state to the assembly station, while supplying the non-elastic, water-impermeable web to the assembly station, a hot-melt adhesive is sprayed on the waistband-disposed portion, and at the assembly station, Characterized in that stretched elastic strips are superposed and adhered to a hot melt adhesive application position on a web. Waistband mounting method of disposable diapers.