JP2017115258A - Ultrasonic jointing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultrasonic jointing device which can easily recognize abnormality and trouble thereof when there is abnormality or trouble in pressure measurement means and the like.SOLUTION: An ultrasonic jointing device 10 including an ultrasonic application device 11 having an ultrasonic horn 14 and an anvil 20 sandwiches an object 1A to be bonded between the ultrasonic horn 14 and the anvil 20, applies ultrasonic vibration thereto, and bonds sheets of the object 1A to be bonded. The ultrasonic jointing device comprises: a position control mechanism in which the ultrasonic horn 14 is advanced and retreated toward the anvil 20 so that the ultrasonic horn 14 can be fixed at a specific position in the advancing/retreating direction; and a displacement sensor 28 which detects the position of the ultrasonic horn. The displacement sensor 28 including a first component 28a of the sensor installed at a component interlocked with the ultrasonic horn 14 and a second component 28b of the sensor supported by a support member not interlocked with the ultrasonic horn measures relative distance between the first component 28a of the sensor and the second component 28b of the sensor to detect the position of the ultrasonic horn 14 in the advancing/retreating direction.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an ultrasonic bonding apparatus.

  An ultrasonic bonding apparatus is known in which ultrasonic vibration is applied to an object to be bonded disposed between an anvil and an ultrasonic horn via an ultrasonic horn so as to fuse the sheets in the object to be bonded ( Patent Document 1). Patent Document 2 describes that an ultrasonic bonding apparatus is provided with a displacement sensor that detects vibration of an anvil in a non-contact manner, and Patent Document 3 detects the temperature of an ultrasonic horn and based on the temperature. An ultrasonic bonding method for setting welding conditions is described.

JP 2004-330622 A JP 2014-136227 A Japanese Patent No. 3827273

As an ultrasonic bonding apparatus, for example, an apparatus including an ultrasonic oscillator, a converter, a booster, and an ultrasonic horn is widely known. In the ultrasonic bonding apparatus, a high frequency generated by the ultrasonic oscillator is high. The electrical signal of the voltage is converted into mechanical vibration by the piezoelectric element in the converter, and the mechanical vibration is adjusted in amplitude by the booster and transmitted to the ultrasonic horn. The ultrasonic vibration of the ultrasonic horn is converted into the ultrasonic wave. Applied to the object to be bonded between the horn and the anvil or the like, the sheet in the object to be bonded is heated and melted to cause fusion between the sheet materials.
In such an ultrasonic bonding apparatus, a slight difference in the clearance (gap) between the ultrasonic horn and the anvil or the like greatly affects the fusion between sheets in the objects to be bonded. Therefore, for example, when a joint is intermittently formed on a band-shaped workpiece, a pressure measuring unit is provided in the ultrasonic bonding apparatus, and the workpiece is sandwiched between an ultrasonic horn and an anvil. In addition, it is conceivable to measure the pressure applied to the object to be joined and feedback control the clearance between the ultrasonic horn and the anvil so that the pressure becomes constant.

  However, when an abnormality or failure occurs in the pressure measurement means, the clearance between the ultrasonic horn and the anvil cannot be properly controlled, and it is difficult to understand that an abnormality or failure has occurred in the pressure measurement means. Many.

  The subject of this invention is related with the ultrasonic bonding apparatus which can solve the subject of the prior art mentioned above.

  The present invention includes an ultrasonic application device including an ultrasonic horn and an anvil, and applies ultrasonic vibration by sandwiching an object to be bonded between the ultrasonic horn and the anvil, and between the sheets in the object to be bonded. A position control mechanism capable of advancing and retracting the ultrasonic horn toward the anvil, and fixing the ultrasonic horn at a specific position in the advancing and retreating direction, and the ultrasonic horn A displacement sensor for detecting a position, the displacement sensor comprising: a sensor first member provided on a member interlocked with the ultrasonic horn; and a sensor second member supported by a support not interlocked with the ultrasonic horn. And an ultrasonic bonding apparatus that detects a position of the ultrasonic horn in the advancing / retreating direction by measuring a relative distance between the sensor first member and the sensor second member.

  According to the ultrasonic bonding apparatus of the present invention, when an abnormality or failure occurs in the pressure measuring means or the like, the abnormality or failure can be easily recognized.

FIG. 1 is a schematic view showing an embodiment of the ultrasonic bonding apparatus of the present invention. FIG. 1 is a perspective view showing a pants-type disposable diaper that is an example of a pants-type absorbent article manufactured using an embodiment of the ultrasonic bonding apparatus of the present invention. FIG. 3 is a schematic plan view showing a developed and extended state of the pants-type disposable diaper shown in FIG. FIG. 4 is a schematic view of a production process for producing a pants-type disposable diaper using an embodiment of the ultrasonic bonding apparatus of the present invention.

Hereinafter, the present invention will be described based on preferred embodiments with reference to the drawings.
As shown in FIG. 1, an ultrasonic bonding apparatus 10 according to an embodiment of the present invention includes an ultrasonic application device 11 including an ultrasonic horn and an anvil 20.
The ultrasonic application device 11 includes an ultrasonic oscillator (not shown), a converter 12, a booster 13, and an ultrasonic horn 14. An ultrasonic oscillator (not shown) is installed on or outside the support base 25 of the ultrasonic wave application device 11 arranged at a predetermined position in the transport path of the article to be bonded 1A, and is electrically connected to the converter 12. The high-voltage electric signal having a frequency of about 10 kHz to 100 kHz generated by the ultrasonic oscillator is input to the converter 12. The converter 12 includes a piezoelectric element such as a piezoelectric element, and converts an electric signal input from the ultrasonic oscillator into mechanical vibration by the piezoelectric element. The booster 13 adjusts, preferably amplifies, the amplitude of the mechanical vibration emitted from the converter 12 and transmits it to the ultrasonic horn 14. The ultrasonic horn 14 is made of a lump of metal such as an aluminum alloy or a titanium alloy, and is designed to resonate correctly at the frequency used. The ultrasonic vibration transmitted from the booster 13 to the ultrasonic horn 14 is also amplified or attenuated in the ultrasonic horn 14 and is applied to the junction formation scheduled site 40 of the article 1A.

  Application of ultrasonic vibration by the ultrasonic horn 14 is performed on the article 1A to be joined that is sandwiched between the tip surface 14t of the ultrasonic horn 14 and the anvil 20 and pressurized. By applying ultrasonic vibration with the workpiece 1A sandwiched between the ultrasonic horn 14 and the anvil 20, at least one sheet in the workpiece 1A is melted, and between the sheets in the workpiece 1A. Is welded. By this welding, joints are sequentially and intermittently formed on the workpiece 1A that is continuously conveyed.

  An anvil 20 shown in FIG. 1 is an anvil roll that rotates in the direction of arrow a, and seal blocks 21 and 21 are formed at two opposite locations in the circumferential direction. In a preferred example, the front end surface 14t of the ultrasonic horn 14 is a flat surface, whereas the seal block 21 is regularly formed with irregularities. When the side seal portion 4 is formed in the continuous body of articles, a strong joint portion is formed in a predetermined pattern in the side seal portion 4. In addition, as the ultrasonic application apparatus 11, a commercially available ultrasonic horn, a converter, a booster, and an ultrasonic oscillator can be used in combination.

In addition, the ultrasonic bonding apparatus 10 integrally moves the converter 12, the booster 13, and the ultrasonic horn 14 in the direction T along the thickness direction of the article 1 </ b> A, thereby moving the ultrasonic horn 14 forward and backward toward the anvil 20. And a position control mechanism capable of fixing the position of the tip surface 14t of the ultrasonic horn 14 to a specific position in the advance / retreat direction T. As shown in FIG. 1, the position control mechanism can move the movable table 15 slidably along a slide guide 15 a such as a slide shaft or a slide rail, and the movable table 15 to move back and forth, and stop it at a predetermined position. A drive mechanism 16 and a control unit 26 that controls driving of the movable table 15 by the drive mechanism 16 are provided. The control unit 26 includes a personal computer and a programmable logic controller (PLC), and includes a central processing unit, a display unit, an input unit, an interface unit electrically connected to the driving mechanism 16 and various sensors 27 and 28 described later. ing. The drive mechanism 16 advances and retracts the movable table 15 in the advance / retreat direction T along the thickness direction of the article 1A based on a command from the control unit 26. The drive mechanism 16 that moves the ultrasonic horn 14 in the advancing / retreating direction T is preferably driven by a motor, and is preferably driven by a stepping motor or a servo motor, particularly a stepping motor, from the viewpoint of highly accurate positioning.
In the stepping motor, for example, the number of steps corresponding to the range from the position where the ultrasonic horn 14 is most retracted to the position where it is most advanced is about 7000 to 10,000, and the position of the ultrasonic horn 14 in the forward / backward direction T is 1 μm or less. It can be controlled with accuracy. As the drive mechanism 16, for example, a linear actuator in which a lead screw and a stepping motor are combined, an air cylinder, a hydraulic cylinder drive actuator, or the like can be used.

In addition, the ultrasonic bonding apparatus 10 includes a pressure sensor 27 between the drive mechanism 16 and the movable table 15. The pressure sensor 27 is electrically connected to the control unit 26, and the ultrasonic horn 14 is bonded to the bonded object 1 </ b> A supported by the anvil 20 against the tip surface 14 t of the ultrasonic horn 14. The pressure received from 1A is measured. This measurement is performed every time the workpiece 1A is sandwiched between the ultrasonic horn 14 and the anvil 20. When the pressure applied to the workpiece 1A is less than a predetermined value or a predetermined range, the drive mechanism 16 is driven to advance the ultrasonic horn 14, and when the pressure is higher than the predetermined value or the predetermined range. When the drive mechanism 16 is driven so as to retract the ultrasonic horn 14 and the pressure applied to the article 1A is within a predetermined value or within a predetermined range, the ultrasonic horn 14 is not driven without driving the drive mechanism 16. Maintain the position.
According to the ultrasonic bonding apparatus 10 of the present embodiment, for example, by performing such control, ultrasonic vibrations are applied to all the bonding portion formation scheduled sites 40 of the workpiece 1A with the same clearance. It is possible to suppress the occurrence of uneven bonding strength between a plurality of joints that are intermittently formed in the flow direction of the article 1A.

  The ultrasonic bonding apparatus 10 also includes a displacement sensor 28 that detects the position of the ultrasonic horn 14. As shown in FIG. 1, the displacement sensor 28 includes a receiving member 28 a as a sensor first member provided on a member interlocked with the ultrasonic horn 14, and a support (not shown) that does not interlock with the ultrasonic horn 14. A sensor main body 28b as a sensor second member that is supported and is opposed to the receiving member 28a to detect the position of the ultrasonic horn 14 is provided. Here, interlocking with the ultrasonic horn 14 means that when the ultrasonic horn 14 or the movable table 15 on which the ultrasonic horn 14 is moved in the forward / backward direction T by the drive mechanism 16 described above, the ultrasonic horn 14 moves with them. The phrase “not interlocked with the ultrasonic horn 14” means that when the ultrasonic horn 14 or the movable base 15 on which the ultrasonic horn 14 is mounted is moved in the forward / backward direction T by the drive mechanism 16 described above, it does not move.

  In the example shown in FIG. 1, the receiving member 28 a has a plate shape and is fixed to an upper wall (not shown) of the holder 29 fixed on the movable table 15 by an arbitrary fixing means such as a bolt. The holder 29 has a pair of side walls 29a located on both sides of the ultrasonic horn 14, a front wall (not shown) connecting the front ends of the pair of side walls, and a pair of the side walls and upper edges of the front walls. Has an upper wall (not shown) fixed to the periphery. In the front wall, an opening 29b is formed from one side wall through the front wall to the other side wall, and the direction along the direction orthogonal to the conveying direction of the workpiece 1A is more than the distance between the pair of side walls. The ultrasonic horn 14 having a wide width is fixed with a pair of L-shaped metal fittings 35 and 35 fixed at the top and bottom of the opening 29b on the front wall with the rear portion inserted into the opening 29b. Yes. The pair of L-shaped metal fittings 35, 35 may be ones that fix the ultrasonic horn 14 just by sandwiching the ultrasonic horn 14, and screws or the like penetrating the L-shaped metal fittings are provided in the ultrasonic horn 14. It may be screwed into the screw hole. The ultrasonic horn 14 has a nodal point, and the pair of L brackets 35 and 35 fix the ultrasonic horn 14 at the nodal point. Therefore, ultrasonic vibrations are not transmitted to the pair of L metal fittings 35 and 35 and the holder 29 to which the pair of L metal fittings 35 and 35 are fixed. An annular holding member 36 is fitted around the converter 12, and the lower surface of the holding member 36 is joined to the movable table 15. As the ultrasonic horn 14, one having claw portions at the top and bottom of the nodal point and sandwiching and fixing each of the top and bottom claw portions between a holder body and a member fastened to the holder body with a screw or the like is used. This is also preferable from the viewpoint of suppressing the ultrasonic vibration from being applied to the displacement sensor 28.

On the other hand, the sensor main body 28b is provided to be opposed to the receiving member 28a. The sensor body 28b is fixed to, for example, an inclined or horizontal arm that is fixed at an angle to a column that is vertically set on the floor surface. As the sensor body 28b, an ultrasonic distance sensor, a laser distance sensor, a distance sensor such as an infrared distance sensor, or the like can be used, but an eddy current displacement sensor is preferably used. When using the eddy current displacement sensor, a metal plate or the like can be used as the receiving member 28a. The receiving member 28a may be selected according to the type of distance sensor to be used. Preferably, when an ultrasonic distance sensor, a laser distance sensor, or an infrared distance sensor is used as the distance sensor, A laser or an infrared ray that can reflect infrared rays is used.
If an eddy current displacement sensor is used as the distance sensor, even if paper dust or the like is scattered around, the distance between the sensor main body 28b and the receiving member 28a can be accurately measured. The tip surface 14t of the ultrasonic horn 14 can be detected from the distance and the distance between the receiving member 28a and the tip surface 14t of the ultrasonic horn 14.
When an eddy current displacement sensor is used as the sensor body 28b, the area of the surface of the receiving member 28a facing the sensor body 28b side is preferably at least three times the area of the bottom surface on the receiving member 28a side, more preferably. Is 3 to 5 times the area of the bottom surface.

According to the ultrasonic bonding apparatus 10 of the present embodiment, as described above, based on the pressure detected using the pressure sensor 27 described above, the position of the ultrasonic horn 14 or between the anvil 20 and the ultrasonic horn 14 is used. The joint 4 can be formed by sequentially applying ultrasonic vibration to the joint formation scheduled portion 40 of the band-shaped article 1A while controlling the clearance. If the pressure sensor 27 becomes abnormal or malfunctioned during the steady operation and the clearance based on the pressure cannot be controlled, for example, the clearance between the anvil 20 and the ultrasonic horn 14 is in an appropriate range. This makes it impossible to perform appropriate ultrasonic fusion.
In that case, the distance between the sensor main body 28b and the receiving member 28a or the appropriate range of the position of the ultrasonic horn 14 in the advancing / retreating direction T obtained from the distance is determined by the clearance between the anvil 20 and the ultrasonic horn 14. By setting in advance corresponding to the appropriate range, the anvil 20 and the ultrasonic wave are determined based on the distance between the sensor main body 28b and the receiving member 28a or the position of the ultrasonic horn 14 in the forward / backward direction T obtained from the distance. It can be determined whether or not the clearance with the horn 14 is outside the appropriate range. Such setting of the appropriate range and determination of whether or not the correction range is out of this can be automatically performed by incorporating a predetermined program into the control unit 26 in a personal computer, a programmable logic controller or the like. . The displacement sensor 28 may be one that can indirectly determine the position of the ultrasonic horn 14 based on the distance between the sensor main body 28b and the receiving member 28a.

In the ultrasonic bonding apparatus 10 of the present embodiment, the position of the ultrasonic horn detected by the displacement sensor 28 is out of the appropriate range set based on the appropriate range of the clearance between the anvil 20 and the ultrasonic horn 14. Sometimes it is preferable to provide means for informing about this. As means for notifying that the outside of the proper range is out, a method of emitting a warning sound from a speaker connected to the control unit 26, a method of emitting a warning lamp connected to the control unit 26, and an ultrasonic bonding apparatus for bonding the object 1A The method of stopping the production line of various products including the process of joining using the method, the method of discharging products out of the proper range, and the like. These may be performed alone or in combination of two or more.
Note that the receiving member 28 a may be fixed to another part of the holder 29 interlocked with the ultrasonic horn 14, or may be fixed to a part other than the holder 29 interlocked with the ultrasonic horn 14. The receiving member 28a is preferably fixed to a portion where the ultrasonic vibration generated by the converter 12 is not transmitted from the viewpoint of eliminating the adverse effects due to the vibration. That is, since the ultrasonic horn 14 is fixed to the holder 29 via a pair of L metal fittings 35 and 35 that fix the ultrasonic horn 14 at the nodal point, the receiving member 28a provided on the holder 29 is subjected to ultrasonic vibration. Is not transmitted.

The ultrasonic bonding apparatus 10 described above can be preferably used to form a side seal portion when, for example, a pant-type absorbent article having a side seal portion is manufactured.
FIG. 2 is an example of a pants-type absorbent article having a side seal portion formed using the ultrasonic bonding apparatus 10. A pants-type disposable diaper 1 (hereinafter, also simply referred to as “diaper 1”) shown in FIG. 2 includes an absorbent main body 2 and an exterior body that fixes the absorbent main body 2 as shown in FIGS. 3, and a pair of side seal portions 4, 4 formed by joining both side portions A 1, A 1 of the exterior body 3 on the ventral side A and both sides B 1, B 1 of the exterior body 3 on the back side B A waist opening 8 and a pair of leg openings 9, 9 are formed. The exterior body 3 forms the outer surface of the diaper 1 on the non-skin contact surface side.

  The diaper 1 has a longitudinal direction X corresponding to the wearer's front-rear direction and a lateral direction Y orthogonal to the wearer's front-rear direction in a plan view in a developed and extended state as shown in FIG. The diaper 1 can be divided into a crotch part C arranged at the crotch part when worn and a ventral side part A and a back side part B positioned in the longitudinal direction X. In the present specification, the skin contact surface is a surface directed toward the wearer's skin when worn in a pant-type absorbent article or a component thereof (for example, an exterior body, an absorbent main body, etc.), and is non-skin contact The surface is a surface that is directed to the side opposite to the wearer's skin side (clothing side) in the pant-type absorbent article or a component thereof. In the diaper 1, the longitudinal direction X of the diaper 1 coincides with the longitudinal direction of the absorbent main body 2 and the exterior body 3 that are constituent members thereof, and the lateral direction Y is equal to the width direction of the absorbent main body 2 and the exterior body 3. I'm doing it.

  As shown in FIG. 3, the absorbent main body 2 has a vertically long shape in which the length in the vertical direction X is longer than the length in the width direction Y, and a surface sheet (not shown) that forms a skin contact surface. And a back sheet (not shown) that forms a non-skin contact surface, and a liquid-retaining absorbent (not shown) interposed between the two sheets. The absorptive main body 2 is fixed to the central portion of the exterior body 3 such that the longitudinal direction thereof coincides with the longitudinal direction X of the diaper 1 in the expanded and extended state. Here, the expanded and extended state means that the side seal portion is peeled off, the diaper is set in the expanded state, the elastic member of each part is expanded in the expanded diaper, and the design dimensions (the influence of the elastic member is eliminated at all). In this state, it is expanded until it becomes the same size as when expanded in a flat shape.

  As shown in FIGS. 2 and 3, the outer package 3 is disposed on the outer layer sheet 31 that forms the outer surface of the diaper 1 (the non-skin contact surface of the outer package 3), and the inner surface side of the outer layer sheet 31. An inner layer sheet 32 that forms the inner surface of 1 (skin contact surface of the exterior body 3), and a plurality of thread-like or belt-like elastic members 5, 6, and 7 fixed between the sheets 31 and 32 with an adhesive. It is configured to include. In the drawings other than FIG. 2, the illustration of the waistline elastic member 6 is omitted. The two sheets 31 and 32 are joined to each other at a predetermined site by an adhesive or heat seal (not shown).

  On the stomach side A and the back side B of the diaper 1, strip-shaped end fixing sheets 33 are arranged over the entire area in the diaper width direction. The center part of the width direction Y of the diaper 1 is being fixed to the skin contact surface in the edge part of the vertical direction X of the absorptive main body 2 by well-known joining means, such as an adhesive agent, the edge fixing sheet 33, The entire part of the absorbent main body 2 other than the end part or a predetermined part is fixed on the skin contact surface of the inner layer sheet 32 by a known joining means such as an adhesive. In the absorbent main body 2, the entire non-skin contact surface or a predetermined portion is fixed on the inner layer sheet 32 by a known bonding means such as an adhesive, and both ends are externally covered by the end fixing sheet 33. It is fixed to the body 3.

  As the outer layer sheet 31, the inner layer sheet 32, and the end portion fixing sheet 33, various known sheet materials that are conventionally used in the manufacture of disposable diapers and the like can be used, but a nonwoven fabric is used from the viewpoint of touch and flexibility. Is preferred. As the nonwoven fabric, those of various production methods can be used, and examples thereof include an air-through nonwoven fabric, a heat roll nonwoven fabric, a spunlace nonwoven fabric, a spunbond nonwoven fabric, and a melt blown nonwoven fabric. The fibers constituting the nonwoven fabric are preferably synthetic fibers, particularly thermoplastic fibers, but may contain cellulosic fibers such as pulp fibers.

  The pants-type disposable diaper manufacturing method shown in FIGS. 2 and 3 includes a continuous body manufacturing step S1 for manufacturing a diaper continuous body 1A having a configuration in which a plurality of disposable diapers are connected in one direction, as shown in FIG. A sealing step S2 for forming the side seal part 4 by applying ultrasonic vibrations to the formation part 40 of the side seal part of the diaper continuous body 1A obtained in the body manufacturing process by the ultrasonic bonding device 10 described above; The diaper continuous body 1A ′ in which the seal portion 4 is formed has a dividing step S3 for cutting by a known cutting means, whereby the diaper 1 having the above-described configuration having the pair of side seal portions 4 and 4 is obtained. It is done.

  In the continuum manufacturing step S1, the belt-like outer layer sheet 31 and the belt-like inner layer sheet 32 are bonded to each other in a state where elastic members 5 to 7 are interposed between the sheets 31 and 32 by a known method. The strip-shaped outer package 3 is formed in which a plurality of elastic members 5, 6, and 7 are arranged in an expanded state between the strip-shaped sheets 31 and 32. The waist elastic member 5 for forming waist gathers at the peripheral edge of the waist opening 8 and the waistline elastic member 6 for forming waistline gathers at the waistline are introduced in parallel with the flow direction of both sheets 31, 32, and the leg portion The elastic member 7 is disposed while being oscillated through a known oscillating guide (not shown) that reciprocates perpendicularly to the flow direction of the sheets 31 and 32. In FIG. 4, illustration of the waistline elastic member 6 is omitted. Before the superposition of the belt-shaped outer layer sheet 31 and the belt-shaped inner layer sheet 32, a hot-melt adhesive is applied to a predetermined part of one or both of the sheets 31, 32 facing each other. Keep it. Further, if necessary, a plurality of waistline elastic members 6 and a plurality of leg elastic portions are used by using elastic member pre-cut means (not shown) so as to correspond to positions where the absorbent main body 2 described later is disposed. The member 7 is pressed and divided into a plurality of pieces so that the contraction function is not expressed. Examples of the elastic member precut means include an elastic member dividing portion used in the method for manufacturing a composite elastic member described in JP-A-2002-253605.

Next, the absorbent main body 2 manufactured in a separate process is intermittently supplied and fixed on the inner layer sheet 32 constituting the strip-shaped outer package 3. Moreover, the edge part fixing sheet 33 is continuously supplied on the inner layer sheet 32 which comprises the strip | belt-shaped exterior body 3, and it fixes so that the both ends of the absorptive main body 2 may be covered. It is preferable to fix the absorptive main body 2 and the end fixing sheet 33 via an adhesive such as a hot melt adhesive applied to each non-skin contact surface side. Moreover, as shown in FIG. 4, the both sides along the conveyance direction of the strip | belt-shaped exterior body 3 are return | folded, and the 4 layer structure part A2 by the side of a stomach side and the 4 layer structure part B2 by the side of a back side are formed. In addition, before or after the arrangement of the absorbent main body 2, the leg hole 91 is formed inside the annular portion surrounded by the leg elastic member 7 in the belt-shaped exterior body 3. This leg hole forming step can be carried out by using a technique similar to that in a conventional method for manufacturing this type of article, such as a rotary cutter and a laser cutter.
Next, as shown in FIG. 4, the diaper continuous body 1 </ b> A is obtained by folding the strip-shaped exterior body 3 in the width direction of the strip-shaped exterior body 3 together with the absorbent main body 2.

In the sealing step S2, an ultrasonic vibration is applied by the ultrasonic bonding apparatus 10 having the ultrasonic horn 14 to the formation planned portion 40 of the side seal portion of the diaper continuous body thus manufactured as the above-described bonded object 1A. Thus, the side seal portion 4 is formed.
In the division step S3, the diaper continuous body 1A ′ having the side seal part 4 formed as described above is cut by a known cutting means to obtain the diaper 1 having the pair of side seal parts 4 and 4. It should be noted that two side seal portions 4a and 4b that serve as side seal portions of different diapers may be simultaneously formed in the planned portion 40 of the side seal portion after the dividing step, or different diapers may be formed after the dividing step. The two side seal portions 4a and 4b serving as the side seal portions may be sequentially formed using a plurality of the ultrasonic bonding apparatuses 10 described above.

As mentioned above, although this invention was demonstrated based on the embodiment, this invention can be suitably changed without being restrict | limited to the embodiment mentioned above.
For example, an object to be bonded by the ultrasonic bonding apparatus of the present invention preferably includes at least two nonwoven fabrics, and the object to be bonded may include only two nonwoven fabrics bonded to each other. Further, it may be three, four, five or more non-woven fabrics joined together. Moreover, when forming the side seal part 4 of an underpants type absorbent article, you may use one ultrasonic bonding apparatus which has the ultrasonic horn of the width covering the full length of the formation part 40 of a side seal part, A plurality of ultrasonic bonding devices having a sonic horn may be arranged in the width direction of the diaper continuous body to form one side seal portion 4. Further, the receiving member 28a may be a block shape instead of the plate shape.

  For example, in the displacement sensor 28 of the ultrasonic bonding apparatus 10 of the present invention, the receiving member 28a is provided in the holder 29, and the sensor main body 28b is supported by a support body (not shown) that is not interlocked with the ultrasonic horn 14. On the contrary, the sensor main body 28b may be provided in the holder 29, and the receiving member 28a may be supported by a support body (not shown) that is not interlocked with the ultrasonic horn 14.

1 Pants-type disposable diapers (pants-type absorbent articles)
1A diaper continuum (continuous body of pants-type absorbent article)
2 Absorbent body 3 Exterior body 4, 4a, 4b Side seal part (joint part)
DESCRIPTION OF SYMBOLS 5 Waist part elastic member 6 Girth part elastic member 7 Leg part elastic member 8 Waist opening part 9 Leg opening part 10 Ultrasonic bonding apparatus 11 Ultrasonic application apparatus 12 Converter 13 Booster 14 Ultrasonic horn 14t Front end surface of ultrasonic horn 15 Movable Base 16 Drive mechanism 20 Anvil 21 Seal block 22 Rotating shaft 25 Support base 26 Control part 27 Pressure sensor 28 Displacement sensor 28a Receiving member 28b Sensor body 40 Side seal part (joint part) formation planned part S1 Continuous body manufacturing process S2 Seal process S3 Division process

Claims (4)

An ultrasonic application device including an ultrasonic horn and an anvil are provided, an ultrasonic vibration is applied by sandwiching a workpiece between the ultrasonic horn and the anvil, and the sheets in the workpiece are joined together. A sonic bonding apparatus,
A position control mechanism capable of advancing and retracting the ultrasonic horn toward the anvil, fixing the ultrasonic horn at a specific position in the advancing and retreating direction, and a displacement sensor for detecting the position of the ultrasonic horn;
The displacement sensor includes a sensor first member provided on a member interlocked with the ultrasonic horn, and a sensor second member supported by a support not interlocked with the ultrasonic horn, and the sensor first member. And an ultrasonic bonding apparatus that detects a position of the ultrasonic horn in the advancing and retreating direction by measuring a relative distance between the sensor and the sensor second member.   The ultrasonic bonding apparatus according to claim 1, wherein the displacement sensor is an eddy current displacement sensor.   The ultrasonic bonding apparatus according to claim 1, wherein a mechanism for moving the ultrasonic horn forward and backward toward the anvil is driven by a stepping motor or a servo motor. The ultrasonic bonding apparatus according to any one of claims 1 to 3, further comprising means for notifying that a position of the ultrasonic horn detected by the displacement sensor is out of an appropriate range.

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