Dual bonder

This application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/395,152, filed 15 Sep. 2016.

The present invention relates to disposable hygiene products and more specifically, to methods and apparatuses for processing disposable hygiene products such as baby diapers, adult diapers, disposable undergarments, incontinence devices, sanitary napkins and the like. More specifically, the invention relates to controlling and positioning webs or web segments of a disposable diaper and bonding them. Various types of automatic manufacturing equipment have been developed which produce the desired results with a variety of materials and configurations.

The invention disclosed herein relates to a method for controlling pieces traveling on a production line, specifically a bonding system for bonding a plurality of webs together. Although the description provided relates to diaper manufacturing, the method is easily adaptable to other applications. Although the description provided relates to bonding portions of diapers, the method is easily adaptable to other products, other disposable products, other diaper types and other portions of diapers.

The current invention is a system and method for producing a disposable undergarment, with the lateral edges of the undergarment bonded by means of an ultrasonic horn. When a blank is formed for an individual undergarment, the lateral edges of opposing edges of the blank will form the seam. When the edges are sealed together, a seam is formed. The individual undergarments may be later separated along the seams.

FIG. 1 is a schematic view of a system according the present invention.

FIG. 2 is a view similar to that of FIG. 1 , but showing movement of the component parts to vary the distance between bonds.

FIG. 3 is an enlarged view of an anvil insert for use with the present system.

FIG. 3A is an enlarged perspective view of the anvil insert illustrated in FIG. 3 .

FIG. 4 is a top view of the anvil insert illustrated in FIG. 3 .

FIG. 4A is an enlarged view of FIG. 4 and showing a bond pattern.

FIG. 4B is a cross sectional view of the anvil insert illustrated in FIG. 4A , and taken along lines 4 B- 4 B thereof.

FIG. 4C is an enlarged view of FIG. 4A .

FIG. 5 is a top plan view showing a web with spaced apart bonds.

FIG. 6 is a schematic view similar to that of FIG. 1 , and showing webs moving at a non-bonding velocity.

FIG. 6A is a view similar to that of FIG. 6 , but showing a front side and a back side of a folded web.

FIG. 6B is a cross sectional view taken along lines 6 B- 6 B of FIG. 6A , and showing a back side adjacent an anvil and a front side adjacent a horn.

FIG. 7 is a schematic view similar to that of FIG. 6 , and showing movement of accumulator rollers to slow the web to a bonding velocity.

FIG. 8 is a schematic view similar to that of FIGS. 6 and 7 , and showing movement of accumulator rollers to increase the velocity web after bonding.

FIG. 9 is a top plan view of webs moving as illustrated in FIG. 6 .

FIG. 10 is a top plan view of webs moving as illustrated in FIG. 7 .

FIG. 11 is a graphic representation of the various web velocities.

FIG. 12 is a view similar to that of FIG. 1 , but showing three anvils and ultrasonic horns.

FIG. 13 is a view similar to that of FIG. 12 , but showing movement of the component parts to vary the distance between bonds.

FIG. 14 is a top plan view showing paired anvils and ultrasonic horns.

FIG. 15 is a view similar to that of FIG. 14 , but showing movement of the component parts to vary the distance between bonds.

FIG. 16 is a view similar to that of FIGS. 1, 6, and 7 but showing an accumulator series.

FIG. 17 is a view similar to that of FIGS. 1, 6, 7 and 16 but showing another alternative arrangement for the accumulator series.

FIG. 18 is a view similar to that of FIGS. 1, 6, 7, 16 and 17 but showing another alternative arrangement for the accumulator series.

FIG. 19 is a view similar to that of FIGS. 1, 6, 7, 16, 17 and 18 but showing another alternative arrangement for the accumulator series.

Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structures. While the preferred embodiment has been described, the details may be changed without departing from the invention.

With attention to FIGS. 1 and 2 , a bonding system 10 is disclosed wherein the positional accuracy of the bonding and quality of the bonding is improved over the prior art. As shown, the system 10 includes an ultrasonic bonder for bonding a plurality webs 12 , or a folded web 12 having a front side 12 A and a back side 12 B. The system 10 includes a first anvil 14 A, a second anvil 14 B, a first ultrasonic horn 16 A, and a second ultrasonic horn 16 B. The anvils 14 A, 14 B are each provided with an anvil insert 18 having a predetermined profile. The first and second anvils 14 A, 14 B are laterally spaced apart inline and in a machine direction.

The system 10 includes carrying means for carrying the webs 12 so that the webs 12 pass a first gap between the first anvil 14 A and the first ultrasonic horn 16 A and then a second gap between the second anvil 14 B and the second ultrasonic horn 16 B. The first and second ultrasonic horns 16 A, 16 B apply vibration energy to the web 12 simultaneously and in cooperation with a respective anvil 14 A, 14 B to bond a respective portion of the web 12 that is to be an end portion 2 C of an individual finished article (not shown in these views). As mentioned, the first anvil 14 A and the first ultrasonic horn 16 A are provided inline from the second anvil 14 B and the second ultrasonic horn 16 B and are spaced apart a predetermined distance d 1 that corresponds to the distance between bonds 22 . The predetermined distance d 1 may be changed to accommodate various sizes of the finished product, since the distance d 1 corresponds to the length of the individual article. Accordingly, the length of the individual article may be changed by adjusting the position of the first or second ultrasonic horn 16 A, 16 B with respect to the other ultrasonic horn 16 A, 16 B. Moreover, the system 10 includes a device for linear reciprocation of a selected anvil 14 A, 14 B and ultrasonic horn 16 A, 16 B relative another anvil 14 A, 14 B and ultrasonic horn 16 A, 16 B and to move in the direction of arrow A, (see FIG. 2 ) and to thereby change the distance d 1 , d 2 between a selected anvil 14 A, 14 B and horn 16 A, 16 B and the adjacent anvil 14 A, 14 B and horn 16 A, 16 B. Preferably, the selected anvil 14 A, 14 B and ultrasonic horn is 16 A, 16 B slidingly mounted to a base structure (not shown), and its movement manually or computer controlled, as understood by one skilled in the art. Since the distance d 1 , d 2 intervals of bonding positions may be changed by changing the position of the first or second ultrasonic horn 16 A, 16 B, the present system may easily produce individual articles of various sizes. It is to be understood that while the view of FIG. 2 illustrates movement of the second ultrasonic horn 16 B, the position of the first ultrasonic horn 16 A may also or alternatively be changeable, as required by a specific application.

With attention to FIGS. 6-11 , the present system 10 may be seen to further comprise a velocity-changing device for increasing and decreasing the moving velocity of the web 12 . The velocity-changing device preferably includes a first web festoon accumulator 24 A having a first accumulator roller 30 A, and a second web festoon accumulator 24 B having a second accumulator roller 30 B. The first web festoon accumulator 24 A receives the webs 12 flowing from an upstream side and releases the webs toward the ultrasonic horns 16 A, 16 B while the second web festoon accumulator 24 B receives the webs 12 from the ultrasonic horns 16 A, 16 B and moves the webs 12 toward a downstream side. The velocity-changing device further includes means for moving the first and second accumulator rollers 30 A, 30 B in a unison, linear manner to thereby change the velocity V 1 of the web 12 received. As seen in FIG. 7 , when the first and second accumulator rollers 30 A, 30 B move in the direction of arrow B, the velocity V 1 of the web 12 from the upstream side is moved to second, slower velocity V 2 , such that the dwell time of the web 12 during the bonding operation is adequate for proper bonding. The anvil rolls 14 A, 14 B are preferably synchronized such that the device 10 will produce two bonds 22 simultaneously during the slower V 2 velocity. Once the web 12 is bonded, the accumulator rollers 30 A, 30 B move in the direction of arrow C (see FIG. 8 ) and the webs 12 move at velocity V 3 to be ultimately transported by the second web festoon accumulator 24 B at the first V 1 velocity and in a downstream direction.

The surfaces of the anvils 14 A, 14 B used in cooperation with the ultrasonic horns 16 A, 16 B may preferably include an anvil insert 18 , as is shown in FIGS. 3-4C . The anvil insert 18 may include a seal surface, an embossing surface, or a combination thereof. The anvil insert 18 illustrated in these views includes a pair of spaced apart seal surfaces 26 having a recess 28 therebetween and wherein the seal surfaces 26 are provided with a series of canted rectangular patterns or teeth 32 thereon. The canted orientation of the rectangular pattern 32 provides both trailing edge and leading edge coverage in a cross-machine direction. This arrangement allows even wear on the horns 16 A, 16 B interfacing with the anvils 14 A, 14 B such that the need to re-grind worn horns 16 A, 16 B is greatly reduced. Moreover, the cost associated with anvil 14 A, 14 B assembly is reduced because the anvil 14 A, 14 B and the insert 18 may be manufactured separately and less material is required. Further, maintenance of the anvil 14 A, 14 B is easier and less costly since the user requires only a spare insert 18 rather than an entire anvil 14 A, 14 B when replacement is needed. Typical bond patterns produced by typical anvils (not shown) are not canted and are often merely a series of parallel rectangles (not shown). During use, these typical bond patterns may wear grooves into the surface of the horn 16 A, 16 B causing downtime for horn 16 A, 16 B maintenance. The pattern 32 disclosed in FIGS. 4, 4A, 4B and 4C reduces downtime for horn 16 A, 16 B maintenance. With particular reference to FIGS. 4A and 4B , it may be seen that the canted arrangement of the rectangles or teeth 32 , creates a bond pattern that will evenly wear a corresponding ultrasonic horn 16 A, 16 B. As shown, the edges 34 of adjacent teeth 32 are parallel to one another for facile manufacture. Moreover, the teeth 32 are angled relative to the machine direction at a predetermined angle F (see FIG. 4A ) that provides a following tooth 32 to fill in any gaps G (See FIG. 4C ) existing between any preceding tooth 32 . The view of FIG. 4C illustrates this particular feature in greater detail. Depending on the geometry, such as width of gap between teeth 32 rows, width of gap between teeth 32 , and the like, the predetermined angle F may provide full coverage of the ultrasonic horn 16 A, 16 B to achieve the goal of even wear. While angling the teeth 32 provides more even wear of the ultrasonic horn 16 A, 16 B, structural liability of the teeth 32 may increase with the angle F. Structural integrity of the teeth 32 may be increased through the use of various radii between the teeth 32 (see FIG. 4B for example). By varying the radii between the teeth 32 such that each tooth has a small radius R 2 on one side and a large radius R 1 on the other, individual teeth 32 are more structurally sound and the chance of breaking a tooth 32 is greatly reduced. The anvil insert 18 of these views may be used to simultaneously bond adjacent article end portions 20 , while reserving a boundary between the sealed end portions for a later severing operation.

With attention to FIGS. 12-15 , it may be seen that a bonding system 10 according to the present invention may include a first anvil 14 A, a second anvil 14 B, a third anvil 14 C, a first ultrasonic horn 16 A, a second ultrasonic horn 16 B, and a third ultrasonic horn 16 C. The anvils 14 A, 14 B, 14 C may be each provided with an anvil insert 18 having a predetermined profile, as described above. The anvils 14 A, 14 B, 14 C are laterally spaced apart inline and in a machine direction. As in the previous embodiment, the ultrasonic horns 16 A, 16 B, 16 C apply vibration energy to the web 12 simultaneously and in cooperation with a respective anvil 14 A, 14 B, 14 C to bond a respective portion of the web 12 that is to be an end portion 20 of an individual finished article (not shown in these views). As previously described, the first anvil 14 A and the first ultrasonic horn 16 A are provided inline from the second anvil 14 B and the second ultrasonic horn 16 B, with the third anvil 14 C and the third ultrasonic horn 16 C provided inline from the second anvil 14 B and the second ultrasonic horn 16 B. The anvils 14 A, 14 B, 14 C with the corresponding horns 16 A, 16 B, 16 C are spaced apart a predetermined distance d 3 that corresponds to the distance between bonds 22 . The predetermined distance d 3 may be changed to accommodate various sizes of the finished product, since the distance d 3 corresponds to the length of the individual article. Accordingly, the length of the individual article may be changed by adjusting the position of the first, second, or third ultrasonic horn 16 A, 16 B, 16 C with respect to any other ultrasonic horn 6 A, 16 B, 16 C. Moreover, the system 10 includes a device for linear reciprocation of a selected anvil 14 A, 14 B, 14 C and ultrasonic horn 16 A, 16 B, 16 C relative to another anvil 14 A, 14 B, 14 C and ultrasonic horn 16 A, 16 B, 16 C and to move in the direction of arrow D, (see FIG. 13 ) and to thereby change the distance d 3 , d 4 between a selected anvil 14 A, 14 B, 14 C and horn 16 A, 16 B, 16 C and the adjacent anvil 114 A, 14 B, 14 C and horn 16 A, 16 B, 16 C. As in the previously described arrangement, a selected anvil 14 A, 14 B, 14 C and ultrasonic horn is 16 A, 16 B, 16 C is preferably slidingly mounted to a base structure (not shown), and the movement manually or computer controlled, as understood by one skilled in the art. Since the distance d 3 , d 4 intervals of bonding positions may be changed by changing the position of the first, second, or third ultrasonic horn 16 A, 16 B, 16 C the present system may easily produce individual articles of various sizes. It is to be understood that while the views of FIGS. 12 and 13 illustrate movement of the first and third ultrasonic horns 16 A, 16 C, the position of the second ultrasonic horn 16 B may also or alternatively be changeable, as required by a specific application. Moreover, the bonding system 10 may include any combination of fixed and moveable ultrasonic horns 16 A, 16 B, 16 C, such as, but not limited to: one fixed ultrasonic horn, with two movable ultrasonic horns; two fixed ultrasonic horns and one movable ultrasonic horn; three fixed ultrasonic horns; and three movable ultrasonic horns, by way of non-limiting example.

FIGS. 14 and 15 illustrate another arrangement of anvils and ultrasonic horns. In these views anvil pairs 114 A, 114 B are utilized rather that the single anvils 14 A, 14 B, 14 C illustrated in previous views. Moreover, ultrasonic horn pairs 116 A, 116 B correspond to and cooperate with the anvil pairs 114 A, 114 B.

FIGS. 16 and 17 illustrate an alternative arrangement and showing a vertical accumulator series 140 rather than the web festoon accumulator 24 A, 24 B and accumulator rollers 30 A, 30 B arrangement previously described. As shown, the accumulator series 140 may include any number of roll assemblies 130 . It is to be understood that while specific numbers and arrangements of assemblies 130 are shown in the Figures, any number and arrangement of roll assemblies 130 may be envisioned without departing from the invention. Moreover, while not specifically shown, it is to be understood that the accumulator series 140 shown in FIGS. 16 and 17 may be used with any of the anvils 14 A, 14 B, 14 C and ultrasonic horns 16 A, 16 B, 16 C described and illustrated in previous views.

FIGS. 18 and 19 illustrate an alternative arrangement similar to that of FIGS. 16 and 17 but showing a horizontal accumulator series 140 A. As shown, the accumulator series 140 A may include any number of roll assemblies 130 . As in the arrangements shown n FIGS. 16 and 17 , it is to be understood that the specific number and arrangement of assemblies 130 shown in the Figures should not be considered limiting, and any number and arrangement of roll assemblies 130 may be envisioned without departing from the invention. Moreover, while not specifically shown, it is to be understood that accumulator series 140 A shown in FIGS. 18 and 19 may be used with any of the anvils 14 A, 14 B, 14 C and ultrasonic horns 16 A, 16 B, 16 C described and illustrated in previous views.

The foregoing is considered as illustrative only of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.