Manufacturing method and manufacturing equipment of composite sheet of absorbent article

A manufacturing method of a composite sheet of an absorbent article, the method includes joining a continuous body of an elastic member in a predetermined meander pattern in respect to a continuous body of a sheet transported continuously in a transporting direction, the method includes: transporting the continuous body of the sheet by wrapping the continuous body of the sheet around an outer circumferential face of a transporting roll that rotates in a direction along the transporting direction; and joining the continuous body of the elastic member to a portion of the continuous body of the sheet wrapped around the transporting roll by feeding the continuous body of the elastic member to the continuous body of the sheet via an oscillating arm that oscillates in an intersecting direction intersecting the transporting direction with a spindle portion as a swivel fulcrum, wherein the oscillating arm includes an oscillating end side roller arranged at an oscillating end side of the oscillating arm and a spindle portion side roller arranged at a spindle portion side, wherein in the joining, the continuous body of the elastic member supplied toward the spindle portion side roller through a supply route along a rotational central axis direction of the spindle portion is put around an outer circumferential face of the spindle portion side roller and an outer circumferential face of the oscillating end side roller successively and guided to the continuous body of the sheet, and a driving force to make the oscillating arm oscillate is input at a position on the oscillating arm different from the spindle portion.

RELATED APPLICATIONS

The present application is a national phase of PCT/JP2010/055541, filed Mar. 29, 2010 and is based on, and claims priority from, Japanese Application Number 2009-091504, filed Apr. 3, 2009.

TECHNICAL FIELD

The present invention relates to manufacturing methods and manufacturing equipment of composite sheets of absorbent articles.

BACKGROUND ART

A disposable diaper and the like have conventionally been known as an example of an absorbent article that absorbs body waste fluid. In its manufacturing line, a continuous body of a sheet that is transported continuously in a transporting direction is attached continuously with a continuous body of an elastic member in a meander pattern such as a sine curve.

As an example of such an attaching method, Patent Literature 1 discloses that a continuous body of the elastic member211is attached to a sheet213using an oscillating arm203that swivels and oscillates around a rotational central axis C201of a predetermined spindle portion201as shown in a side view ofFIG. 1A, and a B-B cross sectional view ofFIG. 1Aas shown inFIG. 1B. That is, a through hole is provided at an oscillating end203aof the oscillating arm203, and a continuous body of the elastic member211is passed through this through hole. With the oscillating movement of the oscillating arm203around the rotational central axis C201, the oscillating end203ais oscillated in a CD direction that intersects the transporting direction of the sheet213, thereby a continuous body of the elastic member211is attached in a predetermined meander pattern in respect to the sheet213that is transported in the transporting direction.

Further, PTL 1 also discloses a driving mechanism of the oscillating arm203, that is, there is described that a drive rotational shaft of a motor205is directly connected concentrically to a spindle portion201of the oscillating arm203.

CITATION LIST

Patent Literature

SUMMARY OF INVENTION

Technical Problem

Here, a continuous body of the elastic member211is directly sent to the through hole of the oscillating end203aof the oscillating arm203from a guide roller207supported by a portion other than the oscillating arm203. Thus, in the case where an amplitude amount of oscillation of the oscillating arm203is large, there is fear that a travel state of the continuous body of the elastic member211becomes unstable, such as it becomes likely for the continuous body of the elastic member211to fall of the guide roller207.

From the view of stability of this travel state, as in the side view ofFIG. 2A, and the B-B cross sectional view inFIG. 2Ashown inFIG. 2B, it is considered effective to support a guide roller207ain a portion to the spindle portion201side in the oscillating arm203, and at the time of supplying the continuous body of the elastic member211toward the guide roller207a, to make a supply route P211follow along a direction of a rotational central axis C201of the spindle portion201.

Further, at the upper side of the spindle portion201, it is possible to set the above described preferable supply route P211as shown inFIG. 2A. However, as shown inFIG. 2Ain a chain double-dashed line, there is a case where the preferable supply route211has to be set at a lower side of the spindle portion201.

But, in this case, the motor205is provided at the lower side of the spindle portion201, so that the motor205gets in the way, and it becomes difficult to set the above preferable supply route P211.

The invention has been made in view of the problems described above, and an advantage is that it is possible to easily set a supply route of a continuous body of an elastic member that goes toward a spindle portion along a rotational central axis direction of the spindle portion of an oscillating arm, and thereby to improve travel stability of the continuous body of the elastic member.

Solution to Problem

In order to achieve the above-described advantages, an aspect of the invention is a manufacturing method of a composite sheet of an absorbent article, the method including joining a continuous body of an elastic member in a predetermined meander pattern in respect to a continuous body of a sheet transported continuously in a transporting direction, the method including:

transporting the continuous body of the sheet by wrapping the continuous body of the sheet around an outer circumferential face of a transporting roll that rotates in a direction along the transporting direction; and

joining the continuous body of the elastic member to a portion of the continuous body of the sheet wrapped around the transporting roll by feeding the continuous body of the elastic member to the continuous body of the sheet via an oscillating arm that oscillates in an intersecting direction intersecting the transporting direction with a spindle portion as a swivel fulcrum,

wherein the oscillating arm includes an oscillating end side roller arranged at an oscillating end side of the oscillating arm and a spindle portion side roller arranged at a spindle portion side,

wherein in the joining, the continuous body of the elastic member supplied toward the spindle portion side roller through a supply route along a rotational central axis direction of the spindle portion is put around an outer circumferential face of the spindle portion side roller and an outer circumferential face of the oscillating end side roller successively and guided to the continuous body of the sheet, and

wherein a driving force to make the oscillating arm oscillate is input at a position on the oscillating arm different from the spindle portion.

Another aspect of the invention is a manufacturing equipment of a composite sheet of an absorbent article, the equipment including joining a continuous body of an elastic member in a predetermined meander pattern in respect to a continuous body of a sheet transported continuously in a transporting direction, the equipment including:

a transporting roll that rotates in a direction along the transporting direction and transports the continuous body of the sheet by wrapping around the continuous body of the sheet on an outer circumferential face; and

an oscillating armthat oscillates in an intersecting direction intersecting the transporting direction with a spindle portion as a swivel fulcrum andthat joins the continuous body of the elastic member to a portion of the continuous body of the sheet wrapped around the transporting roll by feeding the continuous body of the elastic member to the continuous body of the sheet,

wherein the oscillating arm includes an oscillating end side roller arranged at an oscillating end side of the oscillating arm and a spindle portion side roller arranged at a spindle portion side,

wherein the continuous body of the elastic member supplied toward the spindle portion side roller through a supply route along a rotational central axis direction of the spindle portion is put around an outer circumferential face of the spindle portion side roller and an outer circumferential face of the oscillating end side roller successively and guided to the continuous body of the sheet, and

wherein a driving force to make the oscillating arm oscillate is input at a position on the oscillating arm different from the spindle portion.

Other features of the present invention will be made clear through the present specification with reference to the accompanying drawings.

Advantageous Effects of Invention

According to this invention, it is possible to easily set a supply route of a continuous body of an elastic member that goes toward a spindle portion along a rotational central axis direction of the spindle portion of an oscillating arm, and thereby can improve travel stability of the continuous body of the elastic member.

DESCRIPTION OF EMBODIMENTS

At least the following matters will become clear through the description of the present specification and the accompanying drawings.

A manufacturing method of a composite sheet of an absorbent article, the method including joining a continuous body of an elastic member in a predetermined meander pattern in respect to a continuous body of a sheet transported continuously in a transporting direction, the method including:

transporting the continuous body of the sheet by wrapping the continuous body of the sheet around an outer circumferential face of a transporting roll that rotates in a direction along the transporting direction; and

joining the continuous body of the elastic member to a portion of the continuous body of the sheet wrapped around the transporting roll by feeding the continuous body of the elastic member to the continuous body of the sheet via an oscillating arm that oscillates in an intersecting direction intersecting the transporting direction with a spindle portion as a swivel fulcrum,

wherein the oscillating arm includes an oscillating end side roller arranged at an oscillating end side of the oscillating arm and a spindle portion side roller arranged at a spindle portion side,

wherein in the joining, the continuous body of the elastic member supplied toward the spindle portion side roller through a supply route along a rotational central axis direction of the spindle portion is put around an outer circumferential face of the spindle portion side roller and an outer circumferential face of the oscillating end side roller successively and guided to the continuous body of the sheet, and

wherein a driving force to make the oscillating arm oscillate is input at a position on the oscillating arm different from the spindle portion.

With this manufacturing method of the composite sheet of the absorbent article, it is possible to oscillate the oscillating arm without directly connecting concentrically a drive rotational axis of the driving source of the oscillating arm in respect to the spindle portion. Thus, the driving source does not have to be arranged close to the spindle portion, and as a result the continuous body of the elastic member can be easily supplied toward the spindle portion through the supply route along the rotational central axis direction of the spindle portion.

Further, the portion at the spindle portion side of the oscillating arm is provided with the spindle portion side roller, and the continuous body of the elastic member is fed to the spindle portion side roller along the rotational central axis direction of the spindle portion. Thus, the movement in the intersecting direction of the continuous body of the elastic member that may occur due to the oscillating movement of the oscillating arm appears mainly as a torsion in the portion of the continuous body of the elastic member positioned at the upstream side than the spindle portion side roller and is absorbed there, and for this reason falling off of the continuous body of the elastic member from the spindle portion side roller is effectively prevented. As a result, stability in the travel state of the continuous body of the elastic member is obtained.

A manufacturing method of a composite sheet of an absorbent article, wherein preferably

the oscillating end side roller and the spindle portion side roller are arranged on a face of the oscillating arm on a side opposing the transporting roll,

the spindle portion is formed with a communicating space that communicates the side opposing the transporting roll and a side not opposing the transporting roll, along the rotational central axis direction of the spindle portion,

the continuous body of the elastic member that is fed through the supply route along the rotational central axis direction of the spindle portion reaches a face of the oscillating arm on the side not opposing the transporting roll, and ends at the spindle portion side roller by passing through the communicating space.

With this manufacturing method of the composite sheet of the absorbent article, in the case where the continuous body of the elastic member is fed toward a face of the oscillating arm that is at a side opposite the face on which the spindle portion side roller is provided (namely, the surface on a side not opposing the transporting roll), it becomes possible to surely put the continuous body of the elastic member around the spindle portion side roller, by passing it through the communicating space of the spindle portion.

A manufacturing method of a composite sheet of an absorbent article, wherein preferably

the communicating space is a through hole formed in the spindle portion along the rotational central axis direction of the spindle portion.

With this manufacturing method of the composite sheet of the absorbent article, in the case where the continuous body of the elastic member is fed toward a face of the oscillating arm that is at a side opposite the face on which the spindle portion side roller is provided (namely, the face on a side not opposing the transporting roll), it becomes possible to surely put the continuous body of the elastic member around the spindle portion side roller, by passing it through the communicating space of the spindle portion.

A manufacturing method of a composite sheet of an absorbent article, wherein preferably the rotational central axis of the spindle portion is in contact with

an outer circumferential face of the spindle portion side roller.

With this manufacturing method of the composite sheet of the absorbent article, the rotational central axis of the spindle portion is contacting the outer circumferential face of the spindle portion side roller. Thus, the continuous body of the elastic member is surely fed to the spindle portion side roller along a rotational central axis direction of the spindle portion. As a result, a movement in the intersecting direction of the continuous body of the elastic member that may occur due to the oscillating movement of the oscillating arm surely appears as torsion in the portion of the elastic member that is to the upstream side than the spindle portion side roller and is absorbed there. As a result, falling off of the continuous body of the elastic member from the spindle portion side roller can be effectively prevented.

A manufacturing method of a composite sheet of an absorbent article, wherein preferably

in order to input the driving force to the oscillating arm,a driving source having a drive rotational axis that is rotatingly driven anda conversion transmission mechanism that converts a rotating movement of the drive rotational axis to a reciprocating movement and transmits the reciprocating movement to the position on the oscillating arm

are included,

the conversion transmission mechanism havinga rotating member attached integrally to the drive rotational axis anda coupling member that couples the position on the oscillating arm to a position eccentric from the drive rotational axis of the rotating member, and

the rotating member is set with a plurality of the eccentric positions each having different eccentric amounts from each other.

With this manufacturing method of the composite sheet of the absorbent article, by selecting the eccentric position on the rotating member, the amplitude amount of the oscillating arm can be changed. Thus, by selecting the eccentric position according to the meander pattern of the elastic member, it is possible to easily change to a desired meander pattern.

A manufacturing method of a composite sheet of an absorbent article, wherein preferably

the transporting roll rotates around a rotational axis,

the oscillating end side roller and the spindle portion of the oscillating arm are arranged so as to sandwich the rotational axis of the transporting roll in between, and

a direction of travel of the continuous body of the elastic member is reversed by the oscillating end side roller and the continuous body of the elastic member is supplied to the transporting roll.

With this manufacturing method of the composite sheet of the absorbent article, it becomes possible to ensure a large wrap around angle of the continuous body of the elastic member to the oscillating end side roller. For this reason, the continuous body of the elastic member can be tightly held on the outer circumferential face of the oscillating end side roller. As a result, stability in the travel state of the continuous body of the elastic member, such as being able to effectively prevent falling off of the continuous body of the elastic member from the oscillating end side roller, is obtained.

Further, in the case where the continuous body of the elastic member is a continuous body of a strip member, the continuous body of the strip member can be fed to the sheet by being maintained in a substantially flat shape, and as a result, the continuous body of the strip member can be made to come in surface contact with the sheet and can be joined. Namely, by reversing the above-described travel direction, the continuous body of the strip members is wrapped around the outer circumferential face of the oscillating end side roller at a large wrap around angle. Therefore, the continuous body of the strip members is restrained in a substantially flat shape by the outer circumferential face, and as a result the continuous body surely comes in surface contact with the sheet and is joined.

A manufacturing method of a composite sheet of an absorbent article, wherein preferably

the spindle portion side roller is supported on the oscillating arm so that an orientation of the roller in respect to the oscillating arm cannot be changed, in a state in which the outer circumferential face of the spindle portion side roller is facing toward the oscillating end of the oscillating arm.

With this manufacturing method of the composite sheet of an absorbent article, the outer circumferential face of the spindle portion side roller faces toward the oscillating end side roller according to the oscillating movement of the oscillating end side roller. Therefore, even if the oscillating end side roller changes its position in the intersecting direction due to the oscillating movement, the continuous body of the elastic member can be surely fed toward the oscillating end side roller. As a result, stability in the travel state of the continuous body of the elastic member, such as effectively preventing falling off of the continuous body of the elastic member from the oscillating end side roller, is obtained.

Further, the outer circumferential face of the spindle portion side roller can be made to always face the oscillating end, so as to completely synchronize with the oscillating movement of the oscillating arm.

A manufacturing method of a composite sheet of an absorbent article, wherein preferably

the intersecting direction is perpendicular to the transporting direction,

the rotational central axis direction of the spindle portion is perpendicular to a rotational axis at which the transporting roll is to be rotated in a direction along the transporting direction,

the oscillating end side roller is arranged so that a rotational axis of the oscillating end side roller is perpendicular to the rotational central axis direction of the spindle portion, and

the spindle portion side roller is arranged so that a rotational axis of the spindle portion is perpendicular to the rotational central axis direction of the spindle portion.

With this manufacturing method of the composite sheet of an absorbent article, orientation of each rotational axis of the transporting roll, the oscillating end side roller, and the spindle portion side roller, is in a perpendicular relationship in respect to the rotational central axis direction of the spindle portion. Therefore, the torsion in the continuous body of the elastic member at the time the continuous body of the elastic member is handed over from the oscillating end side roller to the transporting roll can be suppressed, and the continuous body of the elastic member can be made to surely come in surface contact with the continuous body of the sheet.

A manufacturing equipment of a composite sheet of an absorbent article, the equipment including joining a continuous body of an elastic member in a predetermined meander pattern in respect to a continuous body of a sheet transported continuously in a transporting direction, the equipment including:

a transporting roll that rotates in a direction along the transporting direction and transports the continuous body of the sheet by wrapping around the continuous body of the sheet on an outer circumferential face; and

an oscillating armthat oscillates in an intersecting direction intersecting the transporting direction with a spindle portion as a swivel fulcrum andthat joins the continuous body of the elastic member to a portion of the continuous body of the sheet wrapped around the transporting roll by feeding the continuous body of the elastic member to the continuous body of the sheet,

wherein the oscillating arm includes an oscillating end side roller arranged at an oscillating end side of the oscillating arm and a spindle portion side roller arranged at a spindle portion side,

wherein the continuous body of the elastic member supplied toward the spindle portion side roller through a supply route along a rotational central axis direction of the spindle portion is put around an outer circumferential face of the spindle portion side roller and an outer circumferential face of the oscillating end side roller successively and guided to the continuous body of the sheet, and

wherein a driving force to make the oscillating arm oscillate is input at a position on the oscillating arm different from the spindle portion.

With this manufacturing method of the composite sheet of an absorbent article, the oscillating arm can be oscillated without directly connecting concentrically the drive rotational axis of the driving source of the oscillating arm in respect to the spindle portion. Therefore, the driving source does not have to be arranged close to the spindle portion, and as a result the continuous body of the elastic member can be easily supplied toward the spindle portion through the supply route along the rotational central axis direction of the spindle portion.

Furthermore, the portion at the spindle portion side of the oscillating arm is provided with a spindle portion side roller, and the continuous body of the elastic member is fed to the spindle portion side roller along the rotational central axis direction of the spindle portion. Therefore, movement of the continuous body of the elastic member in the intersecting direction that may occur due to the oscillating movement of the oscillating arm appears mainly as torsion in the portion of the continuous body of the elastic member positioned to the upstream side than the spindle portion side roller and is absorbed there. As a result, falling off of the continuous body of the elastic member from the spindle portion side roller can be effectively prevented. As a result, stability in the travel state of the continuous body of the elastic member is obtained.

The Present Embodiment

A manufacturing method and a manufacturing equipment of a sheet of the present embodiment is applied to, for example, a manufacturing line of a disposable diaper1(corresponds to an absorbent article).

FIG. 3Ais a partially cutaway plan view of a diaper1, andFIG. 3Bis an exploded perspective view of the diaper. Both diagrams show an expanded state in which a front torso area1aand a back torso area1cin a flank portion of a pants-type diaper1are separated.

This diaper1has a longitudinal direction and a width direction and a thickness direction, that are perpendicular to each other, and along the longitudinal direction of the diaper1are defined the front torso area1a, a crotch area1b, and the back torso area1c. Further, the diaper1has in the thickness direction, a fluid permeable surface sheet2, a fluid impermeable back face sheet3, and a fluid-absorbent absorbent body4arranged in between the sheets2,3. The surface sheet2and the back face sheet3are overlapped in a portion extending outward from a peripheral edge of the absorbent body4, and joined to each other by such as a hot-melt adhesive. Thereby, end edge portion flaps11are formed to the front and back in the longitudinal direction and side edge portion flaps12are formed to the left and right in the width direction. Note that, in the crotch area1bof the side edge portion flaps12, are formed around-leg concave portions10that are formed curved inwardly in the width direction, and the diaper1is a substantially hourglass shape overall.

For the surface sheet2, for example, a fluid permeable plastic film or a nonwoven fabric is used.

The back face sheet3has an inner sheet3afacing the surface sheet2, an outer sheet3bfacing the inner sheet3a, and both these sheets3a,3bare in a same shape and same size to each other, and are joined by adhesion or welding. As the inner sheet3a, a liquid impermeable plastic film or a nonwoven fabric is used, and as the outer sheet3b, an air-permeable nonwoven fabric is used.

Each of the end edge portion flaps11of the front and back torso areas1a,1care joined with a torso elastic member16in a stretched state to the surface and back face sheets2,3.

Further, the crotch area1band its proximity is provided with a front elastic strip member21and a back elastic strip member22across and along a width direction of the diaper1. As these elastic strip members21,22, for example, nonwoven fabric having stretchability or strip shaped rubber and the like is used. These elastic strip members21,22each extend in a width direction in a predetermined meander pattern that is curved in a convex shape toward a center line CL that divides the diaper1substantially in half to the front and back in the longitudinal direction, and the elastic strip members21,22are provided in between the inner sheet3aand the outer sheet3bthat structure the back face sheet3and, for example, are joined to an inner face of the outer sheet3bin a stretched state. These front and back elastic strip members21,22cooperate to give elasticity around the around-leg concave portions10.

Note that, here, a sine curve is illustrated as an example as the meander pattern of these elastic strip members21,22, but the meander pattern can be appropriately changed so that the around-leg convex portions10can effectively fit around the leg of the wearer of the diaper.

Further, in order to increase fitting around substantially the entire length of the around-leg concave portion10, as shown inFIG. 4, the elastic strip members21,22may be arranged to intersect each other at the returning portion of each meander pattern, and further in order to weaken the elasticity in the intersecting region R, a portion of the elastic strip members21,22belonging to the intersecting region R can be divided. Incidentally, elasticity of this intersected region R is weakened because if there is elasticity at the absorbent body4portion, creases are formed in the absorbent body4, and there is fear that fluid absorption performance may deteriorate.

Manufacturing Method and Manufacturing Equipment30of a Composite Sheet of this Embodiment

Such a diaper1is to be completed by a base material of the diaper1that is continuously flowing in the manufacturing line being joined and the like with various structural components. The manufacturing method and the manufacturing equipment30of the composite sheet according to this embodiment carry out one of the processes. That is, here the manufacturing method and the manufacturing equipment30are applied in a process of attaching in the above-described meander pattern a continuous body of an elastic strip member121to be the above-described front elastic strip member21(corresponds to a continuous body of an elastic member, herein referred to as an elastic strip member121) and a continuous body of an elastic strip member122to be the above-described back elastic strip member22(corresponds to a continuous body of an elastic member, herein referred to as an elastic strip member122) to a continuous body of a sheet103bto be an outer sheet3bof the above-described back face sheet3(herein referred to as a sheet103b).

FIG. 5Ais a perspective view showing a partially cutaway manufacturing equipment30of this process, andFIG. 5Bis a cross-sectional view taken along B-B inFIG. 5A. Note that, hereinbelow, a width direction of the manufacturing equipment30is referred to as a CD direction or front side-back side. Further, a direction that is perpendicular to the CD direction is referred to as an MD direction. That is, the MD direction is an arbitrary direction in a plane that is perpendicular to the CD direction. Further, regarding the MD direction, as shown inFIG. 5A, the two direction that are perpendicular to each other are defined as an up-down direction (vertical direction) and a left-right direction (horizontal direction). Incidentally, as shown inFIG. 5B, the CD direction is also in a horizontal direction, and is in a perpendicular relation to the left-right direction in the horizontal direction.

This manufacturing equipment30includes (1) a transporting roll50that transports the sheet103bin the MD direction (corresponds to the transporting direction) by wrapping the sheet103baround in a predetermined wrapping angle and rotating, (2) a slitting apparatus40arranged to a left side of the transporting roll50and that divides in two in the center in the CD direction a sheet member120, that is an original sheet made of an elastic strip member that is sent continuously from the left, and forms a pair of elastic strip members121,122, (3) a first guide member60that continuously feeds the elastic strip member121in a stretched state to a portion of the sheet103bthat is wrapped around an outer circumferential face of the transporting roll50and joins them, and (4) a second guide member160that continuously feeds the elastic strip member122in a stretched state to a portion of the same sheet103band joins them.

These first and second guide members60,160each feed the elastic strip members121,122that they are in charge of toward the sheet103bin the MD direction and reciprocates the elastic strip members121,122in the CD direction (corresponds to an intersecting direction). Thus, each of the elastic strip members121,122are overlapped on the sheet face of the sheet103band joined while the joining position to the sheet103bin the CD direction is changed every moment continuously. As a result, the sheet face of the sheet103bis attached in a surface contact state with a pair of the elastic strip members121,122in an intended meander pattern such as a sine curve.

Incidentally, it is needless to say that before joining each of the elastic strip members121,122to the sheet103b, a hot-melt adhesive is to be applied to each of the elastic strip members121,122by an adhesive applying apparatus that is not shown.

Hereinbelow, each structural element40,50,60,160is described. Note that, in the below description, unless specifically stated, each structural device according to the manufacturing equipment30is cantilevered via an appropriate bracket that is not shown by a vertical support wall92(namely a panel) that extends along an entire length of the manufacturing equipment30in the MD direction. That is, as shown in FIG.5B, at a back side in the CD direction (a back side of a plane of paper inFIG. 5A) is provided the support wall92along a direction substantially parallel to the MD direction (a direction substantially parallel to the plane of paper). A vertical wall face of this support wall92supports portions at the back side in the CD direction of each structural device, and portions at the front side are in a not supported state.

The transporting roll50has a cylindrical body with a rotational axis C50in the horizontal CD direction as a main body, and rotates anti-clockwise in a predetermined peripheral speed in a direction along the MD direction as a rotational direction. This transporting roll50is supplied with the sheet103bfrom the right substantially horizontally, for example. With an approximately 12 o'clock position at an upper portion of the transporting roll50as a wrap around starting position Ps, the sheet103bis wrapped around an outer circumferential face of the transporting roll50, from the position Ps at a wrap around angle of, for example, 180° to 200°, and its transporting direction is reversed. Ultimately, the sheet103bis fed to the right in the substantially horizontal direction, with an approximately 6 o'clock position at a lower portion of the transporting roll50as a wrap around finishing position Pe (corresponds to transporting).

This transporting roll50may be structured as a drive roll that rotatingly drives with an appropriate motor and the like as a driving source, or may be structured as a follower roll that is rotatingly driven by the sheet103b.

A slitting apparatus40has a top and bottom pair of discal rotating blades40a,40bin the center in the CD direction. When passing these rotating blades40a,40b, the sheet member120that is an original plate of the elastic strip members121,122is divided in half, and thereby a pair of the elastic strip members121,122is produced. The elastic strip members121,122are each fed to a first guide member60and a second guide member160.

The first guide member60has a tabular oscillating arm61provided to the left of the transporting roll50. The oscillating arm61is arranged so as to cross over the rotational axis C50of the transporting roll50up and down in the vertical direction. Then, with a spindle portion65positioned lower than the rotational axis C50as a swivel fulcrum, the oscillating end61apositioned above the rotational axis C50can be made to oscillate in the CD direction.

Further, the drive mechanism70of the oscillating movement is a motor72combined with a crank mechanism74, and these will be described later. Further, the spindle portion65is, for example, a shaft body65that protrudes integrally and to the left from a surface on the left side of the oscillating arm61, and is rotatably supported inside an outer cylindrical member66via bearings67. The outer cylindrical member66is fixed to the support wall92via an appropriate bracket that is not shown, and thus the oscillating arm61is supported to be able to swivel around a rotational central axis C65of the spindle portion65.

On a right side surface of the oscillating arm61that is a surface on a side opposing the transporting roll50are rotatably supported a pair of rollers63,64each around substantially horizontal rotational axes C63, C64. One of the roller63is an oscillating end side roller63provided on an oscillating end61a, and the other roller64is a spindle portion side roller64provided at a position toward the spindle portion65side than the oscillating end side roller63.

Thus, the elastic strip member121of the elastic strip members121,122fed from the above-described slitter apparatus40is first fed from the left to the right along the horizontal direction, and then the elastic strip member121passes a through hole65hformed passing through within the spindle portion65in the horizontal direction (this through hole65hwill be described later) and out a right side surface of the oscillating arm61. Then, the elastic strip member121is put around an outer circumferential face of the spindle portion side roller64that has been set on the same surface to be guided to an upper oscillating end61a. Then, the elastic strip member121is wrapped around an outer circumferential face of the oscillating end side roller63at the oscillating end61a, and after its travel direction has been reversed substantially downward by the wrapping around, the elastic strip member121is supplied from upper left of the transporting roll50to a wrap around range Ps to Pe of the sheet103b.

Then while supplying the elastic strip member121, the oscillating end side roller63reciprocates in the CD direction due to an oscillating movement of the oscillating end61a. Thereby the elastic strip member121is joined to the sheet face of the sheet103bin an intended meander pattern by continuously changing the joining position in the sheet surface of the sheet103bin the CD direction. Further, at the time of supplying the elastic strip member121, the elastic strip member121is restrained to a substantially flat shape by being wrapped around the outer circumferential face of the spindle portion side roller64and the outer circumferential face of the oscillating end side roller63, so that the elastic strip member121is joined in respect to the sheet103bin a surface contacting state (corresponds to joining).

Further, as shown inFIG. 5B, each of the oscillating end side roller63and the spindle portion side roller64is arranged on a straight line L1that connects the oscillating end61aand the rotational central axis C65of the spindle portion65. Further, the oscillating end side roller63is fixed to the oscillating arm61so that its outer circumferential face is facing toward the rotational central axis C65of the spindle portion65and its orientation in respect to the oscillating arm61cannot be changed. On the other hand, the spindle portion side roller64is also fixed to the oscillating arm61so that its outer circumferential face is facing toward the oscillating end61aof the oscillating arm61and its orientation in respect to the oscillating arm61cannot be changed.

Thus, with this structure, according to the reciprocating movement of the oscillating end side roller63, the outer circumferential face of the spindle portion side roller64is always facing toward the oscillating end side roller63, so that the elastic strip member121can be surely fed toward the oscillating end side roller63. As a result, stability of the travel state of the elastic strip member121can be obtained, such as the elastic strip member121falling off from the oscillating end side roller63can be effectively prevented.

Further, according to the above structure, the rotational axis C63of the oscillating end side roller63and the rotational axis C64of the spindle portion side roller64are always maintained in a parallel state, regardless of the oscillating movements of the oscillating arm61. Thus, a difference in tension that applies on both end edges of the elastic strip member121in the width direction that might occur due to the oscillating movements of the oscillating arm61can be surely alleviated, and as a result, the elastic strip member121falling off from the oscillating end side roller63and the spindle portion side roller64can be effectively prevented.

Further, in order to obtain stability in the travel state, as shown inFIG. 5A, a supply route R121of the elastic strip member121to the spindle portion side roller64is aligned in a straight line to the rotational central axis C65of the spindle portion65, and the roller64is arranged so that the outer circumferential face of the spindle portion side roller64is in contact with the rotational central axis C65of the spindle portion65. Thus, movement of the elastic strip member121in the CD direction that may occur due to the oscillating movement of the oscillating arm61, appears mainly as a torsion in the portion121aof the elastic strip member121at an upper side than the spindle portion side roller64and is absorbed there, and as a result the elastic strip member121falling off from the roller64can be effectively prevented.

Further, according to this structure, the spindle portion side roller64is arranged so that the outer circumferential face of the spindle portion side roller64is in contact with the rotational central axis C65of the spindle portion65, so that a travel amount of the roller64in the CD direction that may occur with the oscillating movement of the oscillating61can be made to approximately zero, and thus the elastic strip member121falling off from the roller64can be effectively prevented.

Incidentally, in this embodiment, as the drive mechanism70of the oscillating arm61, a so-called direct drive, namely, a structure in which the spindle portion65is directly connected with a drive rotational axis72aof a driving source such as a motor is not used, and the driving force of the driving source is transferred to the oscillating arm61via the crank mechanism74. This is due to the following two reasons.

The first reason is to ensure the above described preferable supply route R121regarding the supply of the elastic strip member121. Described in more detail, as shown inFIG. 5A, in relation to the arrangement position of the slit apparatus40, the elastic strip member121is supplied from the left of the oscillating arm61. However, the spindle portion65is positioned to the left of the oscillating arm61. Therefore, in the case where the drive rotational axis72aof the motor72is matched with the spindle portion65and connected directly, this motor72gets in the way and it becomes difficult to set the preferable supply route R121of the elastic strip member121as described above, that is a supply route R121that is aligned in a straight line with the rotational central axis C65of the spindle portion65.

On the contrary, in the case where a driving force of the oscillating movement of the oscillating arm61is to be input to a position PP different from the spindle portion65by the crank mechanism74, as in this embodiment shown inFIG. 5A, by forming the through hole65hin respect to the spindle portion65substantially concentrically as the rotational central axis C65of the spindle portion65, and also passing through the elastic strip member121in the through hole65h, the supply route R121of the elastic strip member121aligned in a straight line with the rotational central axis C65of the spindle portion65described above can be secured. As a result, the travel state of the elastic strip member121can be stabilized. Note that, such a through hole65hcan be expressed as a communicating space for communicating a side opposing the transporting roll50(right side) and a side not opposing the transporting roll50(left side). Further, it is needless to say that the oscillating arm61is also formed with a through hole61hin the left to right direction so as to correspond with the through hole65h.

The second reason is to increase movement stability in oscillation of the oscillating arm61. Namely, in the case where the crank mechanism74is used, at the time of making the oscillating arm61perform the oscillating movement, the drive rotational axis72aof the motor72needs only to be rotated in one direction, that is, the drive rotational axis72aof the motor72does not have to be rotated in the forward and reverse direction. As a result, since at least switching control does not lie in the rotation direction of the motor72, stability in the oscillating movement of the oscillating arm61becomes outstanding.

Such a crank mechanism74(corresponds to a conversion transmission mechanism) has on a drive rotating axis72aof the motor72in a horizontal direction in the MD direction a circular disk member75(corresponds to a rotating member) that has been fixed integrally and concentrically and a rod-shaped link member76(corresponds to a connecting member) that connects the disk member75and a power point PP of the oscillating arm61. Then, a position eccentric from a drive rotating axis72ain the disk member75is connected with an end portion of the link member76by a coupling pin78or the like. Thus, every time the disk member75rotates once, the link member76is reciprocated once only in its longitudinal direction, and the oscillating arm61performs an oscillating movement only once by this one reciprocating movement.

Note that, here, as connecting positions of the link member76in the disk member75, there may preferably be prepared a plurality of positions P75, P75. . . , and moreover these plurality of positions P75, P75. . . may be different from each other in their eccentric amounts that is a distance to the drive rotating axis72a. If it is set in this way, it is possible to easily change an amplitude amount of the oscillating movement of the oscillating arm61by selecting each connecting position P75, P75. . . on the disk member75. Thus, if each connecting position P75, P75. . . is set in advance corresponding to the size of the disposable diaper1, thereafter the operator needs only to select the connecting position P75of a size to be manufactured next, to be able to switch easily and immediately to a meander pattern corresponding to the relevant size. Thus, it becomes possible to remarkably shorten a down time that accompanies size changing of the disposable diaper1.

Further, as in the example inFIG. 5B, preferably each of the connecting positions P75, P75. . . may be set in positions different from each other in regard to a circumferential direction of the disk member75. In the illustrated example, a rotation radius that is an eccentric amount of the connecting positions P75, P75. . . are gradually decreased as it progresses along one direction in the circumferential direction of the disk member75, as if these connecting positions P75, P75. . . exist on one whirl line in appearance. In the case where positions in the circumferential direction of each of the connecting positions P75, P75. . . are different from each other in this way, supposing that in the case where a difference in an eccentric amount of one connecting position P75and an eccentric amount of another connecting position P75is small, interference of the connecting positions P75, P75. . . from each other can be effectively avoided.

For example, in the case where the coupling pin78is used to connect the disk member75and the link member76, it is necessary to provide pin holes to the disk member75side, and it is possible to avoid these pin holes from becoming connected to each other. Thus, it is possible to change the eccentric amounts of these connecting positions P75in small increments, and as a result it is possible to change the amplitude amount of the oscillating arm61in small increments.

Incidentally, if a curve that connects these connecting positions P75, P75. . . is in a whirl shape as described above, the operator can instantly recognize a size of amplitude corresponded to each connecting position P75based on the aligning order of the connecting positions P75in the circumferential direction of the disk member75. Therefore, it is possible to decrease frequency in occurrence of selecting mistakes of the connecting position P75at the time of changing the size.

By the way, as shown inFIG. 5B, the power point PP of the oscillating arm61of this embodiment is provided at a position that is at an opposite side to the oscillating end61aof the oscillating arm61sandwiching a rotational central axis C65of the spindle portion65. That is, the oscillating arm61has an extending portion61bthat extends toward an opposite side of the oscillating end61afrom the spindle portion65, and a power point PP is set at an end portion of the extending portion61b. An end portion of the link member76is connected to this power point PP by a coupling pin78and the like. However, the position of the power point PP is not limited to the above as long as it is at a portion other than the spindle portion65. For example, as shown inFIG. 6, the PP may be set at a portion in between the spindle portion65and the oscillating end61aof the oscillating arm61. Note that, selection of either the structure inFIG. 5Bor the structure inFIG. 6is decided based on the layout of the motor72and the crank mechanism74and the like.

(4) The Second Guide Member160

The second guide member160is a member with roughly the same structure as the above-described first guide member60. As shown inFIG. 5B, the second guide member160is arranged more to the back side than the first guide member60in the CD direction. Thus, the elastic strip member122, that this second guide member160is in charge of, is attached more to the back side in the CD direction than the elastic strip member121and in parallel thereto, the elastic strip member121being attached to the sheet103bby the first guide member60. However, according to the disposable diaper1, as shown inFIG. 4, an arrangement pattern in which the elastic strip member121and the elastic strip member122are partially overlapped is possible. In that case, if the first guide member60and the second guide member160are arranged in parallel, these guide members60,160will come in collision with each other and cannot form the above-described pattern.

Here, in order to avoid the above collision, as shown inFIG. 5A, the position of the second guide member160in a circumferential direction Dc of the transporting roll50is made different from that of the first guide member60. That is, the second guide member161is arranged displaced to an upstream side in the circumferential direction Dc than the first guide member61.

In more detail, as shown inFIG. 5A, the oscillating arm161of the second guide member160is at a position in which the oscillating arm61of the first guide member60is rotatingly moved to an upstream side in the circumferential direction Dc for a predetermined rotating angle θ only around an imaginary axis, that is not shown, parallel to the rotational axis C50of the transporting roll50, the rotating angle θ being 90° in the shown example. Thus, the oscillating arm161is arranged above the first guide member60and the transporting roll50, and striding over the rotational axis C50of the transporting roll50to the left and right in the horizontal direction. With the spindle portion165that is positioned more to the left of the rotational axis C50as a swivel fulcrum, the oscillating end161apositioned more to the right than the rotational axis C50is structured so as to be able to oscillate in the CD direction.

The driving mechanism170for the oscillating movement is the motor172combined with the crank mechanism174, as in the case for the first guide member160. Further, the spindle165is a shaft body165that extends integrally and upwards from an upper surface of the oscillating arm161, as similar to the case with the first guide member160, and this shaft body165is supported rotatably in an outer cylindrical member166via the bearings167. Note that, the outer cylindrical member166is fixed to the support wall92.

Further, on a lower surface of the oscillating arm161which is a surface on a side opposing the transporting roll50, each of a pair of rollers163,164is rotatably supported around horizontal rotating axes C163, C164. One roller163is an oscillating end side roller163provided at an oscillating end161a, and another roller164is a spindle portion side roller164provided more to the spindle portion165than the oscillating end side roller163.

Therefore, the elastic strip member122that is fed from the slitter apparatus40is fed from the left to the right in the horizontal direction, while being in parallel in the CD direction next to the elastic strip member121that is sent to the above-described first guide member60. At a position in which a rotational central axis C165of the spindle portion165of the second guide member160matches a plan position, a travel direction of the elastic strip member122is changed upwards in the vertical direction by a direction changing roller190to reach the spindle portion side roller164, and is put around the outer circumferential face of the spindle portion side roller164. Then, with the spindle portion side roller164, the elastic strip member122is guided to the oscillating end161athat is to the right than the transporting roll50, and thereafter, after the travel direction is reversed to the left by the oscillating end side roller163at the oscillating end161a, the elastic strip member122is supplied close to the wrap around starting position of the sheet103bfrom the upper right of the transporting roll50.

Then, during the above supplying, the oscillating end side roller163reciprocates in the CD direction due to the oscillating movement of the oscillating end161a, thus the elastic strip member122is joined to a sheet face of the sheet103bin a desired meander pattern with its joining position in the sheet face of the sheet103bbeing continuously changed in the CD direction. Further, at the time of this supply, the elastic strip member122is restrained in a substantially flat shape by wrapping around the outer circumferential face of the spindle portion side roller164and an outer circumferential face of the oscillating end side roller163, so that the elastic strip member122is joined to the sheet103bin a surface contact state.

Note that, the structure shown in below (a) to (c) are all the same as those for the first guide member60, and therefore their detailed description is omitted.

(a) Each of the oscillating end side roller163and the spindle portion side roller164are arranged on a straight line that connects the oscillating end161aof the oscillating arm161and the rotational central axis C165of the spindle portion165.

(b) The oscillating end side roller163is fixed to the oscillating arm161so that its outer circumferential face is facing toward the rotational central axis C165of the spindle portion165of the oscillating arm161with its orientation in respect to the oscillating arm161being unable to be changed and the spindle portion side roller164is also fixed to the oscillating arm161so that its outer circumferential face is facing toward the oscillating end161aof the oscillating arm161with its orientation in respect to the oscillating arm161being unable to be changed.

(c) The supply route R122of the elastic strip member122to the spindle portion side roller164is aligned in one line with the rotational central axis C165of the spindle portion165, and the spindle portion side roller164is arranged so that the circumferential face of the spindle portion side roller164is contacting the rotational central axis C165of the spindle portion165.

Other Embodiments

The embodiments of the present invention have been described above, but the present invention is not limited to the embodiments, and below modifications are possible.

In the above-described embodiment, the crank mechanism74(174) is illustrated as a conversion transmission mechanism that transfers the rotating movement of the drive rotating axis72aof the motor72by converting it to a reciprocating movement to the oscillating arm61(161), and the power point PP is set to an end portion of the extending portion61bof the oscillating arm61. As long as a power point PP is set at a position different from the spindle portion65(165) however, it is not limited thereto.

For example, as shown inFIG. 7, the drive rotational axis72aof the motor72may be arranged in parallel in respect to the spindle portion65, with pulleys81,82provided fixed to both the spindle portion65and the drive rotational axis72a, and an endless belt79may be put around these pulleys81,82, and a driving force that is needed for the oscillating movement of the oscillating arm61may be transferred from the drive rotational axis72ato the spindle portion65via the endless belt79. Note that, in this case, it is needless to say that the drive rotational axis72ais to be controlled to repeat a forward and reverse rotation.

Further, as a driving source to drive the oscillating arm61(161), a cylinder in which a piston appears by an appropriate working fluid such as a hydraulic fluid or air may be used. In this case, for example, on the one hand the piston is to be connected to the oscillating arm61(161), whereas the cylinder is to be attached to the support wall92via an attaching mechanism that can oscillate such as a trunion or a crevice shape.

In the above-described embodiment, the manufacturing method of a composite sheet according to this invention is applied for manufacturing of the pants type diaper1, but it is not limited thereto and may be applied for manufacturing of expanding type diapers (a type of diaper in which the front torso area1aand the back torso area1care held fixed by a tape fastener when wearing).

In the above-described embodiment, there is illustrated a structure in which an oscillating arm61(161) has two rollers of an oscillating end side roller63(163) and a spindle portion side roller64(164), but it is not limited thereto, and one roller may be provided in between the oscillating end side roller63(163) and the spindle portion side roller64(164). Note that, in this case the rotating axis of the roller to be additionally provided may be in parallel to the rotational axis C64(C164) of the spindle portion side roller64(164).

In the above-described embodiment, as shown inFIG. 5A, the rotational central axis C65of the spindle portion65of the first guide member60is oriented in the left-right direction (horizontal direction), the rotational central axis C165of the spindle portion165of the second guide member160is oriented in the up-down direction (vertical direction), and the rotational axis C50of the transporting roll50is oriented in the CD direction (horizontal direction). However, it is not limited thereto, as long as the rotational central axis C65(C165) of the spindle portion65(165) of the first guide portion60or the second guide portion160and the rotational axis C50of the transporting roll50are in a perpendicular relationship with each other.

In the above-described embodiment, the rotational axis C63(C163) of the oscillating end side roller63(163) and the rotational axis C64(C164) of the spindle portion side roller64(164) are in the substantially horizontal direction. The reason is to hand over the elastic strip member121(122) in a substantially flat shape with little torsion in respect to the transporting roll50with the rotational axis C50in the horizontal direction that is the CD direction. Thus, the orientation of the rotational axes C63(C163), C64(C164) of the oscillating end side roller63(163) and the spindle portion side roller64(164) is not limited to a substantially horizontal direction in any way, and can be changed according to a direction in which the rotational axis C50of the transporting roll50faces. That is, the rotational axis C63(C163) of the oscillating end side roller63(163) and the rotational axis C64(C164) of the spindle portion side roller64(164) may be arranged so that the face that the rotational axes C63(C163), C64(C164) make with the oscillating movement of the oscillating arm61(161) is to be parallel to the rotational axis C50of the transporting roll50. Furthermore, the oscillating end side roller63(163) and the spindle portion side roller64(164) may be arranged so that the rotational axes C63(C163), C64(C164) become perpendicular to the rotational central axis C65(C165) of the spindle portion65(165) that is in a perpendicular relationship with the rotational axis C50of the transporting roll50.

In the above-described embodiment, a flat bone roll that has a circumferential face that is flat across the width direction (CD direction) of the roller is used as the oscillating end side roller63(163) and the spindle portion side roller64(164), but it is not limited thereto in any way. For example, a crowned roller may be used. This crowned roller refers to a roller with a largest diameter portion of the roller set in a central portion in the width direction. With this roller, the elastic strip member121(122) put around the outer circumferential face is given a centripetal force toward the central portion in the width direction of the roller by the largest diameter portion of the outer circumferential face so that it becomes difficult for the elastic strip member121(122) to fall off from the roller. As an example such a crowned roller, there may be, for example, such as a roller formed with annular ribs along a circumferential direction in only the central portion in the outer circumferential face, or a roller that has a radius that gradually increases from end portions toward the central portion of the outer circumferential face.

In the above-described embodiment, a hot-melt adhesive was applied with an adhesive applying apparatus to the elastic strip members121,122, but it is not limited thereto in any way as long as the sheet103band the elastic strip members121,122can be joined together. For example, the adhesive may be applied to just the sheet103b, or to both the elastic strip members121,122and the sheet103b.

REFERENCE SIGNS LIST