JP2014524265A - Ultrasonic sealing device and ultrasonic sealing method - Google Patents

Abstract

  While forming a plurality of welds at intervals in the conveyance direction of the continuous web by applying ultrasonic vibration to the continuous web while the continuous web of the absorbent article is conveyed on a predetermined linear track It is a sealing device. An ultrasonic horn that emits ultrasonic vibration, an anvil that sandwiches the continuous web from its thickness direction when the ultrasonic horn emits ultrasonic vibration toward the continuous web, and the ultrasonic horn and anvil And a reciprocating linear movement mechanism for moving along a forward path and a return path parallel to the linear trajectory. In the forward path, a constant velocity region is set in which both the ultrasonic horn and the anvil move at the same speed value as the conveying speed value of the continuous web while facing each other in the thickness direction. While moving in the constant velocity region, the ultrasonic horn and the anvil perform sandwiching of the continuous web and release of the sandwiching. The ultrasonic horn emits ultrasonic vibration while the continuous web is sandwiched.

Description

  The present invention relates to an ultrasonic sealing device and an ultrasonic sealing method for welding a continuous web relating to an absorbent article such as a disposable diaper.

  Conventionally, in a manufacturing line for absorbent articles such as disposable diapers (hereinafter referred to as diapers), a plurality of continuous webs such as nonwoven fabrics are continuously transported in a state where a plurality of continuous webs are stacked, with a plurality of intervals in the transport direction. Joining these plural continuous webs by forming a welded portion is performed. As an apparatus for this purpose, Patent Document 1 discloses an ultrasonic sealing device 120 as shown in schematic side views in FIGS. 1A to 1F.

  As shown in FIG. 1A, this ultrasonic sealing device 120 has an ultrasonic horn 130 above the linear conveyance path Tr1a of the continuous web 1a, and below the ultrasonic horn 130 during the welding process. And an anvil 160 for holding the continuous web 1a. The horn 130 supported by the parallelogram link mechanism 135 maintains the long axis direction of the horn 130 arranged along the long side link portion 135L of the parallelogram link mechanism 135 in the vertical direction. The parallelogram link mechanism 135 is configured to circularly move in the vertical plane in accordance with the rotation of the short side link portion 135S, so that the holding surface 130a at the lower end of the horn 130 is in a circular motion. It is always maintained in a state of facing downward (see FIGS. 1A to 1F). Further, the anvil 160 is also supported by the same parallelogram link mechanism 165, that is, the long axis of the anvil 160 arranged along the long side link portion 165L of the parallelogram link mechanism 165 in the vertical direction. While maintaining, it is configured to circularly move in the vertical plane according to the rotation of the short side link portion 165S of the parallelogram link mechanism 165. As a result, the holding surface 160a at the upper end of the anvil 160 is also always kept facing upward during the circular motion (see FIGS. 1A to 1F).

  FIG. 2 shows the track Tr130a of the holding surface 130a on the horn 130 side and the track Tr160a of the holding surface 160a on the anvil 160 during such circular movement. Basically, both the holding surfaces 130a and 160a are substantially circularly moved. I am doing. However, the circular movement of the holding surface 130a on the horn 130 side and the circular movement of the holding surface 160a on the anvil 160 side are opposite to each other in the rotation direction, and these circular movements occur on the transport path Tr1a of the continuous web 1a. The tracks Tr130a and Tr160a intersect each other. Further, the clamping surface 160a on the anvil 160 side is attached to the long side link portion 165L of the parallelogram link mechanism 160 via an appropriate elastic member (not shown), whereby the clamping surface 160a is arranged in the vertical direction. It is supported so as to be elastically displaceable.

  Therefore, when the horn 130 side clamping surface 130a and the anvil 160 side clamping surface 160a face each other over the continuous web 1a in the crossing orbit portion TrC where both the tracks Tr130a and Tr160a intersect (FIG. 1E), While sandwiching the continuous web 1a from above and below between the sandwiching surfaces 130a and 160a, the sandwiching surface 160a on the anvil 160 side is pushed downward by the horn 130, so that the continuous web 1a is sandwiched between the sandwiching surface 130a on the horn 130 side and the anvil. It is smoothly held between the holding surface 160a on the 160 side. During this clamping, ultrasonic vibration is emitted from the clamping surface 130a on the horn 130 side toward the continuous web 1a. As a result, the sandwiched portion of the continuous web 1a is melted. Is formed.

JP-A-7-204223

By the way, as shown in FIG. 2, when these clamping surfaces 130a and 160a pass through the crossed track portion TrC, it is described above that the clamping surface 130a on the horn 130 side pushes the clamping surface 160a on the anvil 160 side downward. However, at this time, the angular velocity of the circular motion of the clamping surface 130a on the horn 130 side and the angular velocity of the circular motion of the clamping surface 160a on the anvil 160 side are equal to each other. Therefore, the peripheral speed of the clamping surface 130a on the anvil 130 side becomes slower than the peripheral speed of the clamping surface 130a on the horn 130 side by the amount corresponding to the decrease in the rotation radius R160a of the clamping surface 160a on the anvil 160 side. Then, the portion of the continuous web 1a sandwiched between the sandwiching surfaces 130a and 160a has a relative speed with respect to at least one of the sandwiching surfaces 130a and 160a. There is a possibility that wrinkles may occur in the continuous web 1a.
Further, if the continuous web 1a slides relative to the clamping surfaces 130a and 160a when ultrasonic vibration is applied from the clamping surface 130a to the continuous web 1a, the welding process may become unstable. .
Further, as shown in FIG. 2, the transport path Tr1a of the continuous web 1a is a straight track, whereas the trajectory of the holding surface 130a on the horn 130 side and the holding surface 160a on the anvil 160 side at the crossing track portion TrC. Each of the tracks has a downwardly convex arc shape and a downwardly concave arc shape, and the mismatch of the track shapes also contributes to the relative slip between the continuous web 1a and the sandwiching surfaces 130a and 160a. There is a possibility of promoting the generation of fine powder and soot and destabilization of the welding process.

  The present invention has been made in view of the conventional problems as described above, and its purpose is to suppress the relative speed (relative slip) between the ultrasonic horn, the anvil and the continuous web during the welding process, It is to suppress the generation of fine powder and wrinkles and to stably form the welded portion.

The main invention for achieving the above object is:
While the continuous web related to the absorbent article is transported along a predetermined linear track, a plurality of welds are formed at intervals in the transport direction of the continuous web by applying ultrasonic vibration to the continuous web. An ultrasonic sealing device,
An ultrasonic horn for emitting the ultrasonic vibration;
When the ultrasonic horn emits the ultrasonic vibration toward the continuous web, the anvil that sandwiches the continuous web from the thickness direction with the ultrasonic horn;
A reciprocating linear movement mechanism for moving the ultrasonic horn and the anvil along an outward path and a return path parallel to the linear trajectory;
In the forward path, a constant velocity region is set in which both the ultrasonic horn and the anvil move at the same speed value as the conveying speed value of the continuous web while facing each other in the thickness direction,
While moving in the constant velocity region, the ultrasonic horn and the anvil perform clamping of the continuous web and release of the clamping,
In the ultrasonic sealing device, the ultrasonic horn emits the ultrasonic vibration while the continuous web is sandwiched.

In addition, while the continuous web related to the absorbent article is transported along a predetermined linear track, by applying ultrasonic vibration to the continuous web, a plurality of welds are provided at intervals in the transport direction of the continuous web. An ultrasonic sealing method for forming,
An ultrasonic horn for emitting the ultrasonic vibration;
When the ultrasonic horn emits the ultrasonic vibration toward the continuous web, the anvil that sandwiches the continuous web from the thickness direction with the ultrasonic horn;
A reciprocating linear movement mechanism that moves the ultrasonic horn and the anvil along an outward path and a return path parallel to the linear trajectory,
In the forward path, both the ultrasonic horn and the anvil are moved at the same speed value as the conveyance speed value of the continuous web while facing each other in the thickness direction;
In moving at the same speed value, the ultrasonic horn and the anvil perform clamping of the continuous web;
Releasing the clamping in moving at the same speed value;
The ultrasonic sealing method characterized in that the ultrasonic horn emits the ultrasonic vibration during the clamping.
Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

  According to the present invention, the relative speed (relative slip) between the ultrasonic horn, the anvil, and the continuous web during the welding process is suppressed, thereby suppressing the generation of fine powder and wrinkles and forming the welded portion stably. It becomes.

FIG. 1 is a schematic side view of a conventional ultrasonic sealing device 120 showing how a welding process is performed in a series of (A) to (F). In the conventional ultrasonic sealing device 120, when the base material 1a is sandwiched between the sandwiching surface 130a of the ultrasonic horn 130 and the sandwiching surface 160a of the anvil 160, the base material 1a, the ultrasonic horn 130, and the anvil 160 are in relative speed. It is explanatory drawing of having. FIG. 3A is an explanatory view of the base material 1a of the diaper 1 conveyed to a sealing portion including the ultrasonic sealing device 20 of the first embodiment, and is a perspective view. Drawing 3B is an explanatory view of substrate 1a of diaper 1 conveyed by a seal part provided with ultrasonic sealing device 20 of a 1st embodiment, and is a perspective view. 4A is a schematic side view of the ultrasonic sealing device 20 according to the first embodiment, FIG. 4B is a view taken along the line BB in FIG. 4A, and FIG. 4C is a view along the line CC in FIG. 4A. FIG. It is an enlarged side view which shows the anvil 60 located in a retracted position partly broken. It is an enlarged side view which shows the anvil 60 located in a clamping position partially broken. It is the schematic perspective view which looked at the lower surface 60d of the anvil 60 from diagonally downward. It is explanatory drawing of the data of the operation pattern of the reciprocating movement operation | movement of the ultrasonic horn 30 and the anvil 60 in the front-back direction, The data for the ultrasonic horn 30 is shown in the upper stage, and the data for the anvil 60 are shown in the lower stage. . It is explanatory drawing of the data of the operation pattern of S size and L size, Comprising: The data for ultrasonic horns 30 are shown in the upper stage, and the data for the anvil 60 are shown in the lower stage. It is a schematic side view of the ultrasonic sealing apparatus 20a of 2nd Embodiment. It is explanatory drawing of the data of the operation pattern for the back module 20M, and the data of the operation pattern for the front module 20M. FIG. 11A to FIG. 11J are schematic diagrams showing how the rear module 20M and the front module 20M of the third embodiment form the welded portion 14 on the base material 1a while performing reverse operations with each other. FIG. It is explanatory drawing of the data of the operation pattern for the back module 20M, and the data of the operation pattern for the front module 20M.

  At least the following matters will become apparent from the description of the present specification and the accompanying drawings.

While the continuous web related to the absorbent article is transported along a predetermined linear track, a plurality of welds are formed at intervals in the transport direction of the continuous web by applying ultrasonic vibration to the continuous web. An ultrasonic sealing device,
An ultrasonic horn for emitting the ultrasonic vibration;
When the ultrasonic horn emits the ultrasonic vibration toward the continuous web, the anvil that sandwiches the continuous web from the thickness direction with the ultrasonic horn;
A reciprocating linear movement mechanism for moving the ultrasonic horn and the anvil along an outward path and a return path parallel to the linear trajectory;
In the forward path, a constant velocity region is set in which both the ultrasonic horn and the anvil move at the same speed value as the conveying speed value of the continuous web while facing each other in the thickness direction,
While moving in the constant velocity region, the ultrasonic horn and the anvil perform clamping of the continuous web and release of the clamping,
The ultrasonic sealing device, wherein the ultrasonic horn emits the ultrasonic vibration while the continuous web is sandwiched.

  According to such an ultrasonic sealing device, in the set constant velocity region, both the ultrasonic horn and the anvil move along the linear orbit of the continuous web at the same speed value as the continuous web, Clamping and releasing the web. Therefore, since the three web speed values of the continuous web, the ultrasonic horn, and the anvil are aligned, the sandwiching process is performed, so that the relative speed (relative slip) between the three webs can be suppressed. . As a result, the occurrence of rubbing and wrinkles can be suppressed, and the welded portion can be formed stably.

Such an ultrasonic sealing device,
A plurality of modules having the ultrasonic horn, the anvil, and the reciprocating linear movement mechanism may be arranged side by side along the linear trajectory.

Such an ultrasonic sealing device,
And having at least a first module and a second module as the plurality of modules,
When the reciprocating linear movement mechanism of the first module performs the forward movement operation, the reciprocating linear movement mechanism of the second module performs the backward movement operation,
When the reciprocating linear movement mechanism of the first module performs a backward movement operation, the reciprocating linear movement mechanism of the second module preferably performs an outward movement operation.
According to such an ultrasonic sealing device, the first module and the second module are in a relationship of performing substantially opposite operations with respect to the reciprocating movement of the ultrasonic horn and the anvil. Therefore, due to the reciprocating movement of these ultrasonic horns and anvils, the inertial forces that can act on the support member such as the end plate supporting the first module and the second module can be offset each other. As a result, it is possible to reduce mechanical vibration that can occur in members disposed around the first module and the second module, such as the support member.

Such an ultrasonic sealing device,
And having at least a first module and a second module as the plurality of modules,
When the reciprocating linear movement mechanism of the first module performs an outward movement operation, the reciprocating linear movement mechanism of the second module performs an outward movement operation,
When the reciprocating linear movement mechanism of the first module performs the backward movement operation, the reciprocating linear movement mechanism of the second module may perform the backward movement operation.

Such an ultrasonic sealing device,
During the clamping, the ultrasonic horn preferably applies a certain amount of ultrasonic vibration energy to the continuous web.
According to such an ultrasonic sealing device, the ultrasonic horn applies a certain amount of ultrasonic vibration energy to the continuous web during clamping. Therefore, it is possible to effectively prevent the melt level from being varied for each welded part due to fluctuations in the conveying speed of the continuous web, and as a result, a welded part having a predetermined weld strength can be stably formed.

Such an ultrasonic sealing device,
A controller for controlling the reciprocating linear movement mechanism;
Under the control of the controller, the reciprocating linear movement mechanism repeatedly moves the ultrasonic horn and the anvil along the forward path and the backward path based on a predetermined operation pattern,
The controller has a plurality of data of the operation patterns different from each other,
The controller selects operation pattern data corresponding to the formation pitch of the welded portion to be formed from the plurality of operation pattern data to control the reciprocating linear movement mechanism. It is desirable to use it.
According to such an ultrasonic sealing device, the controller selects the operation pattern data corresponding to the size of the formation pitch of the welded portion to be formed, and the reciprocating straight line based on the selected operation pattern data. Control the moving mechanism. Therefore, the formation pitch of the welded portions can be easily changed.

Such an ultrasonic sealing device,
The vertical direction of the ultrasonic sealing device is orthogonal to the linear trajectory,
The anvil is preferably located above the ultrasonic horn in the vertical direction.

  According to such an ultrasonic sealing device, it becomes easy to maintain the anvil.

Such an ultrasonic sealing device,
It is desirable that the anvil is configured to be movable in the vertical direction, and the ultrasonic horn is configured to be immovable in the vertical direction.

  According to such an ultrasonic sealing device, since the ultrasonic horn is configured to be immovable in the vertical direction, the number of movable parts related to the clamping operation can be reduced.

Such an ultrasonic sealing device,
It is desirable that the anvil is configured to be immovable in the vertical direction, and the ultrasonic horn is configured to be movable in the vertical direction.

  According to such an ultrasonic sealing device, since the anvil is configured to be immovable in the vertical direction, the number of movable parts related to the clamping operation can be reduced.

Such an ultrasonic sealing device,
Both the anvil and the ultrasonic horn may be configured to be movable in the vertical direction.

Also,
While the continuous web related to the absorbent article is transported along a predetermined linear track, a plurality of welds are formed at intervals in the transport direction of the continuous web by applying ultrasonic vibration to the continuous web. An ultrasonic sealing method,
An ultrasonic horn for emitting the ultrasonic vibration;
When the ultrasonic horn emits the ultrasonic vibration toward the continuous web, the anvil that sandwiches the continuous web from the thickness direction with the ultrasonic horn;
A reciprocating linear movement mechanism that moves the ultrasonic horn and the anvil along an outward path and a return path parallel to the linear trajectory,
In the forward path, both the ultrasonic horn and the anvil are moved at the same speed value as the conveyance speed value of the continuous web while facing each other in the thickness direction;
In moving at the same speed value, the ultrasonic horn and the anvil perform clamping of the continuous web;
Releasing the clamping in moving at the same speed value;
The ultrasonic sealing method, wherein the ultrasonic horn emits the ultrasonic vibration during the clamping.
According to such an ultrasonic sealing method, when both the ultrasonic horn and the anvil move at the same speed value as the conveying speed value of the continuous web, both of them move along the linear trajectory of the continuous web. Meanwhile, the web is clamped and released. Therefore, since the three web speed values of the continuous web, the ultrasonic horn, and the anvil are aligned, the sandwiching process is performed, so that the relative speed (relative slip) between the three webs can be suppressed. . As a result, the occurrence of rubbing and wrinkles can be suppressed, and the welded portion can be formed stably.

=== First Embodiment ===
The ultrasonic sealing device 20 according to the present invention is a device that forms a plurality of welds 14 at a predetermined pitch P1 in the conveyance direction of the continuous web 1a with respect to the continuous web 1a conveyed on the continuous production line. is there. And in this 1st Embodiment, the base material 1a of the underpants type diaper 1 is illustrated as the continuous web 1a.
3A and 3B are explanatory views of the base material 1a of the diaper 1 conveyed to the seal portion including the ultrasonic sealing device 20, and both are perspective views. 3B shows a state immediately before being transferred to the seal portion, and FIG. 3A shows a state immediately before FIG. 3B.

  At the time of FIG. 3A, the base material 1a of the diaper 1 includes a continuous web 2a that becomes the top sheet 2 that should be positioned on the skin side of the wearer, and a continuous web 3a that becomes the back sheet 3 that should be positioned on the non-skin side, .. Are disposed between the continuous webs 2a, 3a, and have absorbent bodies 4, 4... Such as pulp fibers disposed at intervals with a product pitch P1 in the conveying direction. And these three components 2a, 3a, 4 are in a state where they are pasted together and deployed together. The present invention is not limited to the use of these three components 2a, 3a, and 4.

  At this time, the leg-hole opening 8 is already formed between the absorbers 4 and 4 adjacent to each other in the transport direction. An elastic member 6 is attached along the leg opening 8 and the crotch 13 to impart stretchability to the leg opening 8. Furthermore, a waist elastic member 5 that imparts stretchability to the periphery of the waist is also adhered along the end corresponding to the periphery of the waist. The present invention is not limited to the use of these components 5 and 6.

  Then, immediately before the seal portion, the base material 1a in the unfolded state of FIG. 3A is folded in half with the crotch part 13 being the substantially central portion in the width direction as the folding position, It is fed into the seal part in a folded state as shown in FIG. 3B. That is, the part corresponding to the front body 10 of the diaper 1 and the part corresponding to the back body 11 are sent to the seal part in a state where they are superposed vertically.

  However, in the base material 1a of the diaper 1 at this time, the portion corresponding to the front body 10 and the portion corresponding to the back body 11 that are overlapped with each other are still unjoined. Therefore, the ultrasonic sealing device 20 of the seal portion performs a welding process on the portion 1e corresponding to the side end portion 1e around the trunk of the diaper 1 to form the weld portion 14 on the base material 1a. The front body 10 and the back body 11 of the base material 1a are joined together. In addition, this invention is not limited to welding the base material 1a or welding in this position.

  Here, the welding target portion 1e, that is, the portion 1e corresponding to the side end portion around the waist of the diaper 1 appears on both sides of the absorbent body 4 at the product pitch P1 in the transport direction on the base material 1a. Therefore, the ultrasonic sealing device 20 forms the welded portions 14 at the product pitch P1 in the transport direction in the parts 1e on both sides of the absorber 4 in the base material 1a. At this time, as shown in FIG. 3B, in the welded portion 14, at least a pair 14, 14 is formed side by side at positions adjacent to each other in the transport direction for each location 1 e. And the base material 1a in which this welding part 14 was formed is sent to a lower process, and in the lower process, the base material 1a is divided | segmented in order by the position 1c between a pair of welding parts 14 and 14, Thereby, A diaper 1 having an opening around the waist and a pair of leg openings 8, 8 is generated.

  Incidentally, examples of the material of the continuous web 2a of the top sheet 2 and the continuous web 3a of the back sheet 3 include non-woven fabrics, woven fabrics, and films made of a heat-welding material such as a thermoplastic resin, but ultrasonic welding is possible. If it is a simple material, it is not limited to this. Moreover, this invention is not limited to the use in this process in manufacture of the diaper 1. FIG.

  4A is a schematic side view of the ultrasonic sealing device 20, FIG. 4B is a view taken along the line BB in FIG. 4A, and FIG. 4C is a view taken along the line CC in FIG. 4A. . In FIG. 4A, the anvil holding portion 72 and the like are shown broken, and in FIGS. 4B and 4C, hatching that should originally be shown in the cross-section portion is applied to some members in order to prevent complication of the drawing. Are omitted.

  In the following description, the width direction of the production line is also referred to as “CD direction” or “left-right direction”. The CD direction is in the horizontal direction. Of the two directions orthogonal to the CD direction, the vertical direction is also referred to as “vertical direction”, and the horizontal direction is also referred to as “front-rear direction”. Incidentally, the three in the left-right direction, the up-down direction, and the front-rear direction are orthogonal to each other.

  In this ultrasonic sealing device 20, the base material 1a is continuously transported at a predetermined transport speed value V1a in the transport direction by a transport device 90 such as a transport roller 90. In this example, the base material 1a is conveyed along a linear track Tr1a with the thickness direction in the up-down direction and the width direction in the left-right direction, with the front-rear direction as the transport direction. That is, the base material 1a is transported using the straight track Tr1a in the front-rear direction as the transport track Tr1a.

  A controller (not shown) that controls the transfer device 90 receives a synchronization signal to synchronize with other devices on the production line, and performs a transfer operation based on the synchronization signal. This synchronization signal is output from a sensor such as a rotary encoder that measures the conveyance amount of the base material 1a in a device that becomes a reference of a production line (for example, a rotary die cutter device that punches and forms the opening 8 around the leg). The The synchronization signal is a rotation obtained by assigning each rotation angle value of 0 ° to 360 ° in proportion to the conveyance amount, for example, with the conveyance amount for one product diaper (that is, the product pitch P1) as a unit conveyance amount. It is an angle signal. In other words, when only one diaper is transported, a rotation angle value from 0 ° to 360 ° is output, and each time one diaper is transported, a rotation angle value from 0 ° to 360 ° is output periodically. Repeated. However, the synchronization signal is not limited to any rotation angle signal. For example, a digital signal obtained by assigning each digital value of 0 to 8191 to the unit carry amount in proportion to the carry amount may be used as the synchronization signal. Further, a pulse signal having a number of pulses proportional to the carry amount may be used as the synchronization signal, and the rotation angle may be detected by counting the number of pulses of the signal.

  As shown in FIG. 4A, the ultrasonic sealing device 20 includes an ultrasonic horn 30 disposed below the linear transport track Tr1a of the substrate 1a, an anvil 60 disposed above the transport track Tr1a, The ultrasonic horn 30 and the anvil 60 are moved along a forward and backward reciprocating linear movement mechanism parallel to the transport path Tr1a of the base material 1a, and the base material 1a is attached to the ultrasonic horn 30 and the anvil 60. It has a clamping drive mechanism that clamps in the thickness direction from the vertical direction, and a controller 80 that controls these mechanisms.

  Here, the outward path is directed to the front, which is the downstream side in the transport direction of the base material 1a, and both the ultrasonic horn 30 and the anvil 60 are in the thickness direction in a substantially central region of the forward path. A constant velocity region Re that moves at the same speed value as the conveyance speed value V1a of the substrate 1a in a state of facing the substrate 1a is set. Further, while moving in the constant velocity region Re, the ultrasonic horn 30 and the anvil 60 hold the base material 1a and release the holding. Further, during the holding, the ultrasonic horn 30 is ultrasonically vibrated. Is coming out.

  Therefore, according to the ultrasonic sealing device 20, the base material 1a, the ultrasonic horn 30, and the anvil 60 have the same moving speed value in the front-rear direction, and the base material 1a is sandwiched to perform the welding process. It can be carried out. That is, since the relative speed (relative slip) between these three members 30, 60, 1 a during the welding process can be suppressed, it is possible to stably form the welded portion 14 while suppressing the occurrence of rubbing and wrinkles of the base material 1 a. It becomes.

  Incidentally, after the above-mentioned welding process, the ultrasonic horn 30 and the anvil 60 are sequentially stopped and released before the ultrasonic horn 30 and the anvil 60 exit the constant velocity region Re, and thereafter the ultrasonic horn 30 and the anvil 60 move forward. In the limit Pf, the moving direction is quickly reversed from the forward direction to the backward direction, and the moving operation of the backward path is started. When the backward movement reaches the backward limit Pb, which is the start position of the forward path, the movement direction is reversed again from the backward direction to the forward direction, and the forward movement operation is started. The operation | movement which concerns on a series of welding processes which starts from is performed. By repeating these steps, a plurality of welds 14 are formed on the substrate 1a at intervals of the product pitch P1 in the front-rear direction, which is the transport direction.

Hereinafter, the ultrasonic sealing device 20 will be described in detail.
For example, the ultrasonic sealing device 20 is supported in a cantilevered state on a mirror plate 19 as a support member standing on a production line like a wall surface. That is, the end plate 19 is arranged to extend in the up-down direction and the front-rear direction on one side (for example, the left side) of the CD direction of the production line. I support it.

  Here, the ultrasonic sealing device 20 can be divided into the following components in addition to the above-described component divisions. That is, the ultrasonic sealing device 20 includes an ultrasonic horn unit 30U including the ultrasonic horn 30, an anvil unit 60U including the anvil 60, and a controller 80. In the following description, the components 30U, 60U, and 80 will be described for convenience of description. Note that the components corresponding to the “reciprocating linear movement mechanism in the back-and-forth direction” and “clamping drive mechanism” in the above-described component classification will be described as needed when the corresponding components appear.

<<<< Ultrasonic Horn Unit 30U >>>>
The ultrasonic horn unit 30U is provided on the upper surface of the floor plate 32 and a horizontal floor plate 32 fixed to the end plate 19 so as not to move relative to the various kinds of equipment related to the ultrasonic horn unit 30U. Is provided on the upper surface of the floor plate 32, and applies a driving force related to the reciprocating movement in the front-rear direction to the ultrasonic horn 30. And a mechanism 50. The guide member 40 and the front-rear direction driving mechanism 50 described above correspond to a “front-rear direction reciprocating linear movement mechanism”.

  The floor plate 32 is fixed to the end plate 19 at one end edge (left end edge) in the CD direction, and is supported in a cantilever state.

  The guide member 40 is, for example, a linear guide 40. That is, it is fixed to the upper surface of the floor plate 32 so as not to be relatively movable, and is provided with respect to each of the pair of left and right rails 42 and 42 extending in the front-rear direction and the rails 42 and 42, and is relatively movable only in the front-rear direction. And sliders 44, 44 that engage with each other. The ultrasonic horn 30 is fixed to the sliders 44 and 44 through an appropriate support 46 so as not to move relative to each other. As a result, the ultrasonic horn 30 is integrated with the sliders 44 and 44 in the front-rear direction. Guided to reciprocate.

  The front-rear direction drive mechanism 50 includes a motor 52 and a feed screw mechanism 56. The feed screw mechanism 56 converts the rotational operation of the drive rotary shaft 52a of the motor 52 into a linear movement operation in the front-rear direction and transmits it to the ultrasonic horn 30. Here, the ball screw mechanism 56 is used. Yes. That is, the screw shaft 57 of the ball screw mechanism 56 is arranged with its axial direction along the front-rear direction. In this state, the screw shaft 57 is supported at both ends by bearing members 59 and 59 on the upper surface of the floor plate 32. It is supported rotatably. A nut member 58 is screwed into a spiral groove (not shown) on the outer peripheral surface of the screw shaft 57 via a large number of ball-shaped rolling elements (not shown). The ultrasonic horn 30 is fixed via the support base 46. Furthermore, the drive rotating shaft 52a of the motor 52 and the screw shaft 57 are connected concentrically via an appropriate shaft coupling 55. Therefore, when the rotation operation of the drive rotation shaft 52 a of the motor 52 is transmitted to the screw shaft 57 and the screw shaft 57 is rotated, the ultrasonic horn 30 moves in the front-rear direction integrally with the nut member 58.

  The motor 52 is, for example, a servo motor 52, and performs position control based on a position command signal (control signal) transmitted from the outside. That is, the servo motor 52 has an amplifier (not shown) having a position detection element capable of detecting the actual position. Therefore, if an arbitrary position in the front-rear direction is given as the target position, the servo motor 52 moves the ultrasonic horn 30 to the target position in the front-rear direction based on the feedback signal of the actual position from the position detection element of the amplifier. Can move. The target position is transmitted from the controller 80 to the servo motor 52 in the form of a position command signal, and the servo motor 52 operates based on this position command signal.

  As shown in the enlarged side views of FIGS. 5A and 5B, the ultrasonic horn 30 is sandwiched horizontally and flatly adjacent to the lower surface of the substrate 1a so as to sandwich the substrate 1a with the anvil 60 from the thickness direction. It has a surface 30a. Then, ultrasonic vibration generated by the attached ultrasonic vibration generator 31 is transmitted to the clamping surface 30a, and as a result, as shown in FIG. 5B, ultrasonic waves are applied to the base material 1a sandwiched between the anvil 60. Vibration is applied. The sandwiched portion of the substrate 1a is melted by the action of frictional heat generated by ultrasonic vibration, and a welded portion 14 is formed in the portion.

  The generation start of the ultrasonic vibration is performed based on an appropriate trigger signal, but the generation stop is performed by the ultrasonic vibration generation device 31 that detects that a predetermined amount of energy (joule) is input in advance. Do. As a result, it is possible to prevent the melt level from being varied for each welded portion 14 due to fluctuations in the conveyance speed value V1a of the substrate 1a, and as a result, the welded portion 14 having a predetermined weld strength can be stably formed. The trigger signal that defines the generation start timing may be generated, for example, by the controller 80 and transmitted to the ultrasonic vibration generating device 31, or the ultrasonic vibration generating device 31 that receives a synchronization signal. However, it may be generated by self-determination of the trigger signal generation start timing from the synchronization signal. In the first embodiment, the controller 80 generates an ultrasonic generation command signal as a trigger signal and transmits the ultrasonic generation command signal to the ultrasonic vibration generator 31. The transmission timing of this ultrasonic wave generation command signal will be described later.

<<<< Anvil Unit 60U >>>>
The anvil unit 60U is provided on a horizontal top plate 62 fixed to the end plate 19 so as not to be relatively movable so as to support various devices related to the anvil unit 60U, and the lower surface of the top plate 62. A guide member 40AN that guides the reciprocating movement along a straight track, a front-rear direction driving mechanism 50AN that is provided on the lower surface of the top plate 62 and applies a driving force related to the reciprocating movement in the front-rear direction to the anvil 60; A vertical reciprocating mechanism 70 for reciprocating the anvil 60 in the vertical direction, which is the thickness direction of the base material 1a, to sandwich the base material 1a with the sonic horn 30 is provided. The guide member 40AN and the front-rear direction driving mechanism 50AN described above correspond to a “front-rear direction reciprocating linear movement mechanism”, and the up-down direction reciprocating movement mechanism 70 corresponds to a “holding drive mechanism”.

  The top plate 62 is fixed to the end plate 19 at one end edge (left end edge) in the CD direction, and is supported in a cantilevered state. And the guide member 40AN and the front-back direction drive mechanism 50AN are provided in the lower surface of this top plate 62. As shown in FIG. The basic structures of the guide member 40AN and the longitudinal drive mechanism 50AN are substantially the same as those 40 and 50 of the ultrasonic horn unit 30U. That is, the linear guide 40 that is the guide member 40 of the ultrasonic horn unit 30U and the ball screw mechanism 56 that is the feed screw mechanism of the front-rear direction driving mechanism 50 are turned upside down and fixed to the lower surface of the top plate 62. The guide member 40AN and the front-rear direction drive mechanism 50AN in the anvil unit 60U are almost as they are. Therefore, the guide member 40 and the longitudinal drive mechanism 50 of the ultrasonic horn unit 30U are mainly different in the above points, and are otherwise substantially the same in structure, so the guide member 40AN and the longitudinal drive mechanism of the anvil unit 60U are the same. As described above, the various configurations related to 50AN are denoted by the same reference numerals as those of the various configurations of the ultrasonic horn unit 30U, and further denoted by “AN”, and the description thereof is omitted.

  As shown in FIG. 4A, the linear guide 40AN and the ball screw mechanism 56AN of the anvil unit 60U are respectively connected with the linear guide 40 and the ball screw mechanism 56 of the ultrasonic horn unit 30U, so that the transport track Tr1a of the base material 1a is viewed from above and below. These are arranged immediately above the linear guide 40 and the ball screw mechanism 56 of the ultrasonic horn unit 30U so as to be sandwiched (from the thickness direction). Therefore, the anvil 60 that is suspended and supported by the slider 44AN of the linear guide 40AN of the anvil unit 60U is disposed opposite to the ultrasonic horn 30 over the base 1a at a position above the base 1a. Therefore, if the servo motor 52AN of the ball screw mechanism 56AN of the anvil unit 60U is controlled so as to operate in conjunction with the servo motor 52 of the ball screw mechanism 56 of the ultrasonic horn unit 30U, the opposed state to the ultrasonic horn 30 is achieved. The anvil 60 can be reciprocated in the front-rear direction in conjunction with the ultrasonic horn 30 while maintaining the above.

5A and 5B are enlarged side views of the anvil 60 and the ultrasonic horn 30. FIG.
As shown in FIG. 5A, an up / down reciprocating mechanism 70 that reciprocates the anvil 60 in the up / down direction (equivalent to a reciprocating mechanism in the thickness direction) includes an anvil holding portion 72 that holds the anvil 60 so as to be relatively movable in the up / down direction. Have. The anvil holding portion 72 is fixed to the sliders 44AN and 44AN of the linear guide 40AN through an appropriate support base 76 so as not to move relative to each other. As a result, the holding portion 72 holds the anvil 60 while holding the anvil 60. The sliders 44AN and 44AN integrally move back and forth in the front-rear direction.

The anvil holding portion 72 has, for example, a box member 72 as a main body, and an anvil 60 is accommodated in a space inside thereof with play corresponding to the above-described reciprocation in the vertical direction. In addition, a through hole 72h that is slightly larger than the cross-sectional shape of the anvil 60 is formed in the lower wall portion 72d of the box member 72 so that the lower surface 60d related to the clamping surface 60a of the anvil 60 protrudes outward. Further, the anvil 60 has a flange portion 60f that protrudes annularly from the upper end portion to the side, and this flange portion 60f is a peripheral portion of the through hole 72h of the lower surface wall portion 72d of the box member 72. To engage. By this engagement, the downward movement amount of the anvil 60 is limited to a predetermined amount, that is, the anvil 60 is allowed to move up and down only between a predetermined upper limit position and a lower limit position.
Here, as shown in FIG. 5A, at the upper limit position, the anvil 60 faces the lower substrate 1a with a predetermined interval. That is, it is not in contact with the substrate 1a. On the other hand, when descending from the upper limit position to the lower limit position as shown by the white arrow, as shown in FIG. 5B, the anvil 60 contacts the base material 1a and pushes the base material 1a further downward. Thus, the anvil 60 is in a state in which the base material 1a is clamped with a predetermined clamping force with the clamping surface 30a of the ultrasonic horn 30. And if it becomes this clamping state, the further downward movement will be stopped by the ultrasonic horn 30, and the anvil 60 will not actually fall to a lower limit position. Hereinafter, the upper limit position is referred to as a “retraction position”, and the position that is in a clamping state on the way to the lower limit position is also referred to as a “clamping position”.

  On the other hand, as shown in FIG. 5A, between the lower surface 72ud of the upper surface wall portion 72u of the anvil holding portion 72 and the upper surface 60u of the anvil 60 (the surface opposite to the clamping surface 60a of the lower surface 60d of the anvil 60). For example, an air spring 74 is interposed as a drive source for moving the anvil 60 up and down. The air spring 74 has a sealed bag body 74 as a main body. The bag 74 expands when the inside is pressurized by supplying air, and contracts when the inside is depressurized by discharging air. Further, a compression spring 75 is interposed between the lower surface wall portion 72d of the anvil holding portion 72 and the flange portion 60f of the anvil 60, and the anvil 60 always moves toward the upper surface wall portion 72u by the restoring force ( In other words, it is pushed upward. Therefore, the anvil 60 can be reciprocated in the vertical direction with respect to the anvil holding portion 72 by supplying and discharging air to and from the air spring 74 in cooperation with the compression spring 75. That is, when air is supplied to the air spring 74 and pressurized, the anvil 60 moves downward and reaches the clamping position due to the expansion of the air spring 74, thereby sandwiching the base material 1 a with the ultrasonic horn 30 below. (FIG. 5B). On the other hand, when the air is discharged from the air spring 74 and the pressure is reduced, the anvil 60 is pushed back upward by the restoring force of the compression spring 75, thereby returning to the retracted position as the upper limit position (FIG. 5A).

  As an example of a mechanism for realizing air supply / exhaust control to the air spring 74, a compressed air source such as a compressor (not shown) is connected to the air spring 74 through an air flow path such as a pipe, and the compressed air source And a configuration in which a regulator (not shown) such as a pressure regulating valve is arranged in the air flow path between the air spring 74 and the air spring 74.

  The air supply / discharge operation is performed based on an appropriate control signal. This control signal may be generated by the controller 80 and transmitted to the regulator, for example, or the regulator receiving the synchronization signal may generate the control signal itself by judging the supply / discharge operation timing from the synchronization signal. You may do it. In the first embodiment, the controller 80 generates a supply / discharge command signal as a control signal and transmits it to the regulator. This supply / discharge signal is, for example, an ONOFF signal. When the ON state is received, the regulator is pressurized and maintained during reception of the ON state. On the other hand, when the OFF state is received, it is maintained under pressure reduction and reception of the OFF state. To do. In other words, this means that “when the supply / discharge command signal is in the ON state, the anvil 60 is sandwiched between the base material 1a, and when the supply / discharge command signal is in the OFF state, the anvil 60 is sandwiching the base material 1a. It can also be expressed as “to be in a released evacuation state”. Therefore, in the following, such a supply / discharge command signal is also referred to as a “holding command signal”.

  By the way, it has been briefly described above that the clamping surface 60a of the anvil 60 is set on the lower surface 60d of the anvil 60 so as to be opposed to the clamping surface 30a of the ultrasonic horn 30 below. 60a will be described in detail. FIG. 6 is a schematic perspective view of the lower surface 60d of the anvil 60 as viewed obliquely from below. On the lower surface 60d of the anvil 60, a pair of front and rear ribs 61 along the left-right direction corresponding to the CD direction, corresponding to the shape pattern (FIG. 3) of the pair of front and rear welds 14, 14 to be formed on the substrate 1a. 61 is formed. .. Are formed on the surface of each rib 61 at a predetermined pitch in the longitudinal direction, and the top surfaces of these protrusions 61 a, 61 a. It becomes the surface 60a. However, this is only an example, and a sandwiching surface 60a of another form may be employed.

<<< Controller 80 >>>
The controller 80 is an appropriate computer or sequencer, and has a processor and a memory (not shown). The controller 80 receives the above-described synchronization signal. Based on this synchronization signal, the controller 80 controls the longitudinal drive mechanisms 50 and 50AN of the ultrasonic horn unit 30U and the anvil unit 60U, the vertical reciprocating mechanism 70 of the anvil 60, and the like. For example, the position command signal is transmitted as a control signal to the amplifiers of the servo motors 52 and 52AN of the longitudinal drive mechanisms 50 and 50AN of the ultrasonic horn unit 30U and the anvil unit 60U, while the anvil unit 60U is reciprocated in the vertical direction. A clamping command signal (supply / discharge command signal) is transmitted as a control signal toward the regulator of the air spring 74 of the moving mechanism 70, and further, control is performed toward the ultrasonic vibration generator 31 of the ultrasonic horn unit 30U. An ultrasonic generation command signal is transmitted as a signal.
Incidentally, a control program related to the above-described control is stored in advance in the memory of the controller 80. In addition, the memory stores operation pattern data defining the longitudinal reciprocating motion of the ultrasonic horn 30 and the anvil 60, data defining the ON / OFF state of the clamping command signal, and the ultrasonic generation command signal. Data defining transmission timing is also stored in advance. Then, the processor appropriately reads out the corresponding control program and data from the memory as needed, and executes them to control the longitudinal drive mechanisms 50 and 50AN related to the ultrasonic horn unit 30U and the anvil unit 60U, and the anvil unit 60U. The control of the vertical reciprocating mechanism 70 according to the above and the control of the ultrasonic vibration generator 31 according to the ultrasonic horn unit 30U are realized.

FIG. 7 shows an operation pattern of the reciprocating movement of the ultrasonic horn 30 and the anvil 60 in the front-rear direction (a pattern showing a correspondence relationship between the target position of the ultrasonic horn 30 and the anvil 60 in the front-rear direction and the rotation angle value of the synchronization signal). ), The data of the ultrasonic horn 30 is shown in the upper part, and the data of the anvil 60 is shown in the lower part. On the vertical axis, the target position in the front-rear direction is taken, a forward limit Pf is set in the front, and a backward limit Pb is set in the rear. And, of course, in the forward path, it moves from the backward limit Pb to the forward limit Pf, and in the backward path, it moves from the forward limit Pf to the backward limit Pb. Further, the horizontal axis represents the rotation angle value corresponding to the synchronization signal, that is, the unit transport amount corresponding to the product pitch P1 of the substrate 1a is assigned to each value of 0 ° to 360 °. 360 ° is also 0 °.
Further, in FIG. 7, the ON / OFF state of the clamping command signal (supply / discharge command signal) related to the vertical reciprocation of the anvil 60 and the transmission timing of the ultrasonic generation command signal related to the ultrasonic horn 30 are defined. The first rotation angle value as data is also shown.

  The controller 80 acquires the target position corresponding to the rotation angle value of the synchronization signal from the data of the operation pattern in the memory at a predetermined control cycle, and uses the acquired target position data as a position command signal for the ultrasonic horn unit. 30U and the anvil unit 60U are transmitted to the amplifiers of the servo motors 52 and 52AN of the front and rear direction drive mechanisms 50 and 50AN. Then, the amplifiers of the servo motors 52 and 52AN control the servo motors 52 and 52AN so as to move the ultrasonic horn 30 and the anvil 60 to the target position of the position command signal. Both the ultrasonic horn 30 and the anvil 60 reciprocate.

  Here, as can be seen from the comparison between the upper graph and the lower graph in FIG. 7, in this example, the ultrasonic horn covers the entire range of rotation angle values of 0 ° to 360 ° with respect to the reciprocating movement in the front-rear direction. The operation pattern of 30 and the operation pattern of the anvil 60 are completely the same pattern with no phase shift of the rotation angle value between them. Therefore, the ultrasonic horn 30 and the anvil 60 can reciprocate in the front-rear direction in complete interlock with each other while maintaining the state in which the clamping surfaces 30a, 60a face each other over the base 1a. .

  Further, as shown in FIG. 7, the first acceleration / deceleration area, the constant speed area moving at a constant speed value, and the second acceleration / deceleration area are set in the forward path, and the same is applied to the return path. The third acceleration / deceleration area, the constant speed area, and the fourth acceleration / deceleration area are set. Here, the speed value in the constant speed region of the forward path is set to the same value as the conveyance speed value V1a in the front-rear direction of the substrate 1a. That is, this constant speed region is a constant velocity region Re in which the velocity values of the ultrasonic horn 30 and the anvil 60 are equal to the conveyance velocity value V1a of the substrate 1a. Further, the ON state of the pinching command signal is set over a predetermined rotation angle value range RON within a substantially central region of the constant velocity region Re. Furthermore, a first rotation angle value for transmitting an ultrasonic wave generation command signal to the ultrasonic vibration generator 31 is set within the rotation angle value range RON associated with the ON state.

  Therefore, when the rotation angle value indicated by the synchronization signal falls within the above range RON, the controller 80 switches the clamping command signal to the vertical reciprocating mechanism 70 of the anvil unit 60U from the OFF state to the ON state. As a result, the anvil 60 located at the retracted position, which is the upper limit position, descends and clamps the base material 1 a with the clamping surface 30 a of the ultrasonic horn 30. Then, when the rotation angle value of the synchronization signal exceeds the first rotation angle value, the controller 80 transmits an ultrasonic wave generation command signal to the ultrasonic vibration generator 31. Thereby, ultrasonic vibration is emitted from the sandwiching surface 30a of the ultrasonic horn 30, and the portion of the base material 1a sandwiched between the sandwiching surface 30a of the ultrasonic horn 30 and the sandwiching surface 60a of the anvil 60 is melted and welded. 14 is formed. The ultrasonic vibration is automatically stopped by the ultrasonic vibration generator 31 as described above. For example, the ultrasonic vibration generator 31 cumulatively measures the amount of energy (joule) that has been input for each welding process, and stops when it detects that the amount of energy that has been input has reached a specified set value. On the other hand, when the rotation angle value of the synchronization signal is out of the range RON, the controller 80 turns the clamping command signal to the OFF state. As a result, the anvil 60 ascends, and after the holding state of the base material 1a is released, it finally returns to the retracted position that is the upper limit position, and then waits until the holding command signal is switched from the OFF state to the ON state. To do.

  Here, as is clear from the above description and FIG. 7, the range RON of the rotation angle value is completely included in the constant velocity region Re of the forward path. Therefore, the clamping and release of the base material 1a are performed in a state where the longitudinal speed values of the ultrasonic horn 30 and the anvil 60 are equal to the transport speed value V1a of the base material 1a. As a result, no relative speed is generated between them, the occurrence of rubbing and wrinkles is suppressed, and the welded portion 14 can be formed stably.

  By the way, in the example of FIG. 7, the operation pattern of the outward path and the operation pattern of the return path have a mirror image relationship with a rotation angle value of 180 ° as a boundary. That is, except for the fact that the direction is reversed, these operation patterns are the same in terms of the pattern shape, but the present invention is not limited to this. For example, if the ultrasonic horn 30 and the anvil 60 can be restored to the backward limit Pb before the rotation angle value reaches 360 °, the return path operation pattern is not mirror-imaged with the forward path operation pattern. May be.

  In the example of FIG. 7, the operation pattern of the reciprocating motion in the front-rear direction is the same for the ultrasonic horn unit 30U and the anvil unit 60U, but the present invention is not limited to this. That is, in the forward path, a constant velocity region Re in which the longitudinal velocity values of the ultrasonic horn 30 and the anvil 60 are the same as the conveyance velocity value V1a of the substrate 1a can be secured as a rotation angle value within a predetermined range. For example, the operation pattern of the ultrasonic horn unit 30U and the operation pattern of the anvil unit 60U may not be completely the same.

  Furthermore, in the first embodiment, the controller 80 has the data of the reciprocating movement pattern in the front-rear direction separately for the ultrasonic horn unit 30U and the anvil unit 60U. However, the data of one operation pattern may be shared by both of them. In that case, the controller 80 transmits a position command signal generated based on the data of the single operation pattern to both the ultrasonic horn unit 30U and the anvil unit 60U. . Thereby, the ultrasonic horn 30 and the anvil 60 can be reciprocated in perfect synchronization.

  By the way, in general, in the production line of the disposable diaper 1, there is a so-called size change in which the product size of the diaper 1 to be manufactured is changed. In the first embodiment, this size change can be easily dealt with. is there. For example, the operation pattern illustrated in FIG. 7 is stored in advance in the memory of the controller 80 for each product size such as S, M, and L. FIG. 8 shows S-size and L-size operation pattern data as an example. As can be seen from FIG. 8, between these S-size and L-size, between the forward limit Pf and the reverse limit Pb. The distances D and DL are different. That is, the distance D is larger in the L size of the product size larger than the S size.

  And if this distance D changes, the space | interval between the welding parts 14 and 14 formed adjacent to the front-back direction will change. Therefore, if the controller 80 selects the data of the operation pattern according to the product size to be manufactured from now on, the size of the formation pitch in the front-rear direction of the welded portion 14 (that is, welding adjacent in the front-rear direction). It is possible to easily cope with the size change through the change of the distance dimension between the portions 14 and 14.

  Further, when it is desired to change the welding strength of the welded portion 14 according to the product size, the set value of the energy amount (joule) to be input by the ultrasonic vibration generating device 31 in connection with the ultrasonic vibration is set to S. , M, L, etc., can be set for each product size, and the ultrasonic vibration generator 31 may be configured to select a set value according to the product size. Needless to say, the set value of the amount of energy is larger in the L size, which has a larger total area of the welded portion 14, than in the S size.

  In addition, as another method of changing the welding strength in accordance with the above-described product size, for example, the holding force when holding the base material 1a between the ultrasonic horn 30 and the anvil 60 is changed for each product size. Can be mentioned. This clamping force is generated by the pressure of the air spring 74 as described above. Therefore, in order to realize this, for example, a regulator is configured so that the pressurizing force of the air spring 74 can be set with a plurality of set values different from each other, and the regulator is configured according to the product size. What is necessary is just to comprise so that one setting value may be selected from several setting values. Incidentally, you may make it perform both the change of the applied pressure according to this product size, and changing the setting value of the energy amount of ultrasonic vibration according to the above-mentioned product size.

=== Second Embodiment ===
FIG. 9 is a schematic side view of the ultrasonic sealing device 20a of the second embodiment.
In the first embodiment described above, the ultrasonic sealing device 20 has only one set of the module 20M including the ultrasonic horn unit 30U and the anvil unit 60U. However, the present invention is not limited to this. For example, a plurality of modules 20M, 20M... May be arranged side by side along the transport track Tr1a of the substrate 1a. In the example of FIG. 9, two modules 20M and 20M are arranged side by side in the front-rear direction as a plurality of examples. Since the other points are almost the same as those in the first embodiment, the same components are denoted by the same reference numerals, and the description thereof is omitted.

  Here, the modules 20 </ b> M and 20 </ b> M arranged in the front-rear direction perform the same operation with respect to the reciprocating movement in the front-rear direction of the ultrasonic horns 30, 30 and the anvils 60, 60. That is, when the ultrasonic horn 30 and the anvil 60 related to the rear module 20M move in the forward / rearward direction, the ultrasonic horn 30 and the anvil 60 related to the front module 20M also move in the forward direction, When the ultrasonic horn 30 and the anvil 60 related to the rear module 20M move along the forward and backward directions, the ultrasonic horn 30 and the anvil 60 related to the front module 20M are also configured to move along the backward path. Yes. Hereinafter, this is also referred to as “forward operation”.

  Such an ultrasonic sealing device 20a according to the second embodiment in which the two modules 20M and 20M perform forward operations with each other is realized, for example, by configuring as follows. First, the memory of the controller 80 has operation pattern data for the rear module 20M and operation pattern data for the front module 20M as shown in FIG. The data of these operation patterns are completely the same without any phase shift of the rotation angle value between them. The same applies to both the rear module 20M and the front module 20M with respect to the rotation angle value range RON related to the ON state of the clamping command signal and the first rotation angle value that defines the start of ultrasonic vibration generation. Is set.

  In the second embodiment, since there are two modules 20M and 20M, a rotation angle value from 0 ° to 720 ° corresponding to the conveyance amount for two diapers is associated with one cycle of the operation pattern. ing. And these two modules 20M and 20M can mutually cooperate and can form the welding part 14 with the product pitch P1 with respect to the base material 1a of the diaper 1. FIG.

  By the way, in this 2nd Embodiment, although the case where the number of the modules 20M was two was illustrated, it cannot be overemphasized that you may arrange | position 3 or more side by side.

=== Third Embodiment ===
FIGS. 11A to 11J are explanatory views of the third embodiment. Specifically, the state in which both the rear module 20M and the front module 20M form the welded portion 14 on the base material 1a is frame-fed. It is a schematic diagram shown. In the drawing, the welded portion 14 formed by the rear module 20M is indicated by a circle, and the welded portion 14 formed by the front module 20M is indicated by a Δ.

  In the above-described second embodiment, as shown in FIG. 10, the two modules 20M and 20M are performing the same operation in the same manner with respect to the reciprocating movement in the front-rear direction. In this third embodiment, The difference is that the reverse operation is performed.

  That is, as shown in FIGS. 11A to 11J, in the third embodiment, when the ultrasonic horn 30 and the anvil 60 related to the rear module 20M (corresponding to the first module) move in the forward and backward directions. The ultrasonic horn 30 and the anvil 60 related to the front module 20M (corresponding to the second module) move on the return path, while the ultrasonic horn 30 and the anvil 60 related to the rear module 20M move back and forth. When moving, the ultrasonic horn 30 and the anvil 60 related to the front module 20M are configured to move in the forward path.

  And according to such a structure, it originates in the back-and-forth movement of the ultrasonic horn 30 and the anvil 60 in the front-back direction, and the inertia which can act on the end plate 19 which supports these back modules 20M and the front modules 20M. The forces can be canceled with each other, and as a result, the mechanical vibration that can occur in the end plate 19 can be reduced.

  In addition, the ultrasonic sealing device 20b according to the third embodiment in which the two modules 20M and 20M perform the reverse operations with each other is realized by, for example, the following configuration. FIG. 12 is an explanatory diagram showing data such as operation patterns of the modules 20M and 20M.

First, the memory of the controller 80 stores operation pattern data for the rear module 20M and operation pattern data for the front module 20M as shown in FIG. In the operation pattern data, the pattern shapes are the same, but the phases of the rotation angle values are shifted by 360 ° which is a half cycle (one cycle is 720 °). ing. Thereby, the reverse operation described above is realized.
Further, as the phase of the rotation angle value of the operation pattern of the front module 20M shown in the lower part of FIG. 12 is shifted by a half cycle (360 °) with respect to the rear module 20M, the front module 20M is sandwiched. The rotation angle value range RON related to the ON state of the command signal and the first rotation angle value that defines the start of the generation of ultrasonic vibration are also determined from the rotation angle value range RON and the first rotation angle value of the rear module 20M. The phases are shifted by 360 ° which is a half cycle. As a result, even in the front module 20M, the welding process is performed in the constant velocity region Re of the forward path.

=== Other Embodiments ===
As mentioned above, although embodiment of this invention was described, said embodiment is for making an understanding of this invention easy, and is not for limiting and interpreting this invention. Further, the present invention can be changed or improved without departing from the gist thereof, and needless to say, the present invention includes equivalents thereof. For example, the following modifications are possible.

  In the above-described embodiment, the disposable diaper 1 that is attached to a wearing target and absorbs the excretory fluid is cited as an example of the absorbent article. However, any one that absorbs excreted fluid such as urine or menstrual blood is used. For example, a sanitary napkin or a pet sheet that absorbs the excretory fluid of the pet may be used.

  In the above-described embodiment, the linear guides 40 and 40AN and the ball screw mechanisms 56 and 56AN are respectively used as the guide members 40 and 40AN and the longitudinal drive mechanisms 50 and 50AN related to the longitudinal reciprocating linear movement mechanism of the ultrasonic horn 30 and the anvil 60. However, the present invention is not limited to the above as long as the ultrasonic horn 30 and the anvil 60 can be reciprocated along the linear conveyance trajectory Tr1a of the substrate 1a. For example, instead of the rails 42 and 42AN of the linear guides 40 and 40AN, the sliders 44 and 44AN may be slidably engaged with linear grooves (not shown) formed in the floor plate 32 or the top plate 62, By using an appropriate cam mechanism in place of the ball screw mechanisms 56 and 56AN, the rotation operation of the servo motors 52 and 52AN may be converted into a linear movement operation. When the cam mechanism is used, the above-described operation pattern can be realized by setting the cam curve of the cam. Therefore, in some cases, the operation pattern data stored in the memory of the controller 80 is omitted. You can also Further, the connection between the drive rotary shafts 52a and 52AN of the servo motors 52 and 52AN and the screw shafts 57 and 57AN is not limited to the shaft couplings 55 and 55AN. For example, a winding conduction device having a timing belt and a pulley is used. You may connect using.

In the above-described embodiment, the anvil 60 is arranged above the ultrasonic horn 30, but this vertical arrangement relationship may be reversed. That is, the anvil unit 60U having the anvil 60 may be disposed below the ultrasonic horn unit 30U having the ultrasonic horn 30. However, from the viewpoint of maintainability, the first embodiment shown in FIGS. 4A and 5A is preferable to this configuration. The reason is as follows.
For example, in the case of the first embodiment, the ultrasonic horn 30 does not reciprocate in the vertical direction, but the anvil 60 reciprocates in the vertical direction, and has a large number of movable parts such as an air spring 74 for its vertical drive. Inevitably, these movable parts are subject to maintenance. Here, according to the structure of 1st Embodiment of FIG. 4A or 5A, in the operation stop state of the ultrasonic sealing apparatus 20, the anvil 60 is located above the base material 1a, and the ultrasonic horn 30 of FIG. Thus, it is not in a state of being covered with the base material 1a from above, and is generally in a state of being entirely exposed. Therefore, the maintenance worker can easily perform maintenance of the movable part of the anvil 60.

  In the above-described embodiment, the transport track Tr1a in the front-rear direction of the substrate 1a is horizontal. However, the present invention is not limited to this, and may be inclined upward or downward from the horizontal with a predetermined inclination angle. However, in that case, the linear trajectory related to the back-and-forth movement of the ultrasonic horn 30 and the linear trajectory related to the back-and-forth movement of the anvil 60 also have the same inclination corresponding to the inclination angle of the above-described transport track Tr1a. The angle is set to be inclined from the horizontal.

  In the above-described embodiment, as an example of the sandwiching drive mechanism, the ultrasonic horn 30 is configured to be immovable in the vertical direction and reciprocated in the vertical direction of the anvil 60. However, the present invention is not limited to this. Absent. For example, the anvil 60 may be configured to be immovable in the vertical direction, and the ultrasonic horn 30 may be reciprocated up and down by a vertical reciprocating mechanism, and further, the ultrasonic horn 30 and the anvil 60 may be Both of them may be configured to reciprocate in the vertical direction. However, it is preferable that either one of the ultrasonic horn 30 and the anvil 60 is configured to be immovable in the vertical direction because the number of movable parts involved in the clamping operation can be reduced.

  In the above-described embodiment, the air spring 74 is exemplified as the drive source of the up-down reciprocating mechanism 70 that is the clamping drive mechanism, but the present invention is not limited to this. For example, an air cylinder or a hydraulic cylinder may be used, or a feed screw mechanism may be applied.

  In the above-described embodiment, the generation of ultrasonic vibration of the ultrasonic vibration generator 31 is stopped when the apparatus 31 detects that the energy amount (joule) of the input ultrasonic vibration has reached the set value. It was. However, in some cases, it is also assumed that the amount of energy reaches the set value after the holding of the base material 1a by the ultrasonic horn 30 and the anvil 60 is released. As a result, welding is insufficient due to the amount added, and as a result, the welded portion 14 may be insufficient in strength. Therefore, it is desirable to configure as follows. First, the controller 80 receives a signal related to the generation stop from the ultrasonic vibration generating device 31 every time the generation of the ultrasonic vibration is stopped. Then, the controller 80 compares the generation stop time obtained from this signal with the time when the pinching is released, and if the generation stop time is later than the pinching release time, the welding failure occurs. An alarm of occurrence is output to an appropriate alarm device to notify the operator.

  In the description of the above-described embodiment, the perspective relationship between the ultrasonic horn 30 and the anvil 60 with respect to the base material 1a in the released state shown in the enlarged side view of FIG. 5A has not been described in detail, and this point will be described. In this released state, the sandwiching surface 30 a of the ultrasonic horn 30 is closer to the base material 1 a than the sandwiching surface 60 a of the anvil 60. And according to such arrangement | positioning relationship, the anvil 60 descend | falls so that the base material 1a may be clamped, and the pushing amount at the time of pushing the base material 1a toward the ultrasonic horn 30 can be decreased. Thereby, it is possible to suppress the disturbance of the transport track Tr1a of the base material 1a due to the pressing, and as a result, the welded portion 14 can be formed more stably.

1 disposable diaper (absorbent article), 1a base material (continuous web),
1c position, 1e site,
2 top sheet, 2a continuous web, 3 back sheet, 3a continuous web,
4 Absorber, 5 Elastic member, 6 Elastic member, 8 Opening around leg
10 front body, 11 back body, 13 inseam, 14 welded part,
19 End plate, 19a Vertical plane,
20 ultrasonic sealing device, 20a ultrasonic sealing device, 20b ultrasonic sealing device,
20M rear module (first module),
20M front module (second module),
30 ultrasonic horn, 30U ultrasonic horn unit,
30a clamping surface, 31 ultrasonic vibration generator, 32 floor board,
40 linear guide (guide member), 40AN linear guide (guide member),
42 rail, 42AN rail, 44 slider, 44AN slider,
46 support base,
50 longitudinal driving mechanism, 50AN longitudinal driving mechanism,
52 servo motor, 52AN servo motor,
52a drive rotary shaft, 52aAN drive rotary shaft,
55 shaft coupling, 55AN shaft coupling,
56 ball screw mechanism (feed screw mechanism), 56AN ball screw mechanism (feed screw mechanism),
57 threaded shaft, 57AN threaded shaft,
58 nut member, 58AN nut member,
59 bearing member, 59AN bearing member,
60 anvil, 60U anvil unit,
60a clamping surface, 60d lower surface, 60f collar, 60u upper surface,
61 rib, 61a convex part,
62 Top plate,
70 Vertical reciprocating mechanism (thickness reciprocating mechanism),
72 box member (anvil holding part), 72d bottom wall part, 72h through-hole,
72u upper surface wall, 72ud lower surface,
74 Air spring, 76 Support base,
80 controller,
90 Conveying roller (conveying device),
Pb backward limit, Pf forward limit,
Re constant velocity range, RON range, Tr1a transport track (straight track),

Claims (11)

While the continuous web related to the absorbent article is transported along a predetermined linear track, a plurality of welds are formed at intervals in the transport direction of the continuous web by applying ultrasonic vibration to the continuous web. An ultrasonic sealing device,
An ultrasonic horn for emitting the ultrasonic vibration;
When the ultrasonic horn emits the ultrasonic vibration toward the continuous web, an anvil that holds the continuous web from its thickness direction in cooperation with the ultrasonic horn;
A reciprocating linear movement mechanism for moving the ultrasonic horn and the anvil along an outward path and a return path parallel to the linear trajectory;
In the forward path, a constant velocity region is set in which both the ultrasonic horn and the anvil move at the same speed value as the conveying speed value of the continuous web while facing each other in the thickness direction,
While moving in the constant velocity region, the ultrasonic horn and the anvil perform clamping of the continuous web and release of the clamping,
The ultrasonic sealing device, wherein the ultrasonic horn emits the ultrasonic vibration while the continuous web is sandwiched. The ultrasonic sealing device according to claim 1,
An ultrasonic sealing device, wherein a plurality of modules each including the ultrasonic horn, the anvil, and the reciprocating linear movement mechanism are arranged along the linear trajectory. The ultrasonic sealing device according to claim 2,
And having at least a first module and a second module as the plurality of modules,
When the reciprocating linear movement mechanism of the first module performs the forward movement operation, the reciprocating linear movement mechanism of the second module performs the backward movement operation,
The ultrasonic sealing device according to claim 1, wherein when the reciprocating linear movement mechanism of the first module performs a backward movement operation, the reciprocating linear movement mechanism of the second module performs an outward movement operation. The ultrasonic sealing device according to claim 2,
And having at least a first module and a second module as the plurality of modules,
When the reciprocating linear movement mechanism of the first module performs an outward movement operation, the reciprocating linear movement mechanism of the second module performs an outward movement operation,
The ultrasonic sealing device, wherein when the reciprocating linear movement mechanism of the first module performs a backward movement operation, the reciprocating linear movement mechanism of the second module performs a backward movement operation. The ultrasonic sealing device according to any one of claims 1 to 4,
During the clamping, the ultrasonic horn applies a certain amount of the energy of the ultrasonic vibration to the continuous web. The ultrasonic sealing device according to any one of claims 1 to 5,
A controller for controlling the reciprocating linear movement mechanism;
Under the control of the controller, the reciprocating linear movement mechanism repeatedly moves the ultrasonic horn and the anvil along the forward path and the backward path based on a predetermined operation pattern,
The controller has a plurality of data of the operation patterns different from each other,
The controller selects operation pattern data corresponding to the formation pitch of the welded portion to be formed from the plurality of operation pattern data, and selects the selected data from the reciprocating straight line. An ultrasonic sealing device used for controlling a moving mechanism. The ultrasonic sealing device according to any one of claims 1 to 6,
The vertical direction of the ultrasonic sealing device is orthogonal to the linear trajectory,
The ultrasonic seal device according to claim 1, wherein the anvil is positioned above the ultrasonic horn in the vertical direction. The ultrasonic sealing device according to claim 7,
The ultrasonic sealing device according to claim 1, wherein the anvil is configured to be movable in the vertical direction, and the ultrasonic horn is configured to be immovable in the vertical direction. The ultrasonic sealing device according to claim 7,
The ultrasonic sealing device, wherein the anvil is configured to be immovable in the vertical direction, and the ultrasonic horn is configured to be movable in the vertical direction. The ultrasonic sealing device according to claim 7,
Both the anvil and the ultrasonic horn are configured to be movable in the vertical direction. While the continuous web related to the absorbent article is transported along a predetermined linear track, a plurality of welds are formed at intervals in the transport direction of the continuous web by applying ultrasonic vibration to the continuous web. An ultrasonic sealing method,
An ultrasonic horn for emitting the ultrasonic vibration;
When the ultrasonic horn emits the ultrasonic vibration toward the continuous web, an anvil that holds the continuous web from its thickness direction in cooperation with the ultrasonic horn;
A reciprocating linear movement mechanism that moves the ultrasonic horn and the anvil along an outward path and a return path parallel to the linear trajectory,
In the forward path, both the ultrasonic horn and the anvil are moved at the same speed value as the conveyance speed value of the continuous web while facing each other in the thickness direction;
In moving at the same speed value, the ultrasonic horn and the anvil perform clamping of the continuous web;
Releasing the clamping in moving at the same speed value;
The ultrasonic sealing method, wherein the ultrasonic horn emits the ultrasonic vibration during the clamping.

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