Patent Application
20220280348
The invention pertains to the technical field of manufacturing tampon blanks, tampons, specifically digital tampons, and intermediate products thereof. The invention relates to an improved apparatus for shaping the introductory end of a tampon, and a method using such apparatus, as well as the product manufactured by said method and apparatus.
Tampons are well known in the art and are used for feminine hygiene. As such, many tampon manufacturing methods and apparatuses have been disclosed in the prior art. Generally, a distinction is made between folded and rolled tampons. The former has improved absorbent characteristics but possess less strength and are commonly used with an applicator to reduce the chance of tears and other damages to the tampon before insertion. Rolled tampons are slightly less absorbent, but sturdier and can be applied digitally, as opposed to the folded tampons. Furthermore, measures can be taken to increase the absorbency of the rolled tampons.
Tampons comprise a rolled or folded absorbent fiber sheet and a withdrawal string for removal. Tampons are manufactured by rolling or folding multiple-layers. The multiple-layered sheets comprise a layer of absorbent material of a certain length, upon which a strip of web material is bonded which has only a fraction of the length of the layer of the absorbent material, thus creating the multiple-layered sheets.
It is desired to attain a maximal production speed, but one recurring problem is that the machines are often limited in speed during the head-shaping step, as most machines exploit a heating press to impart pressure and heat onto the introductory end of the tampon. These machines are not efficient enough as it requires several hits to correctly shape a tampon head and these machines are often subject to mechanical failure with parasite melting of the thermoplastic film onto the heating plates. For example, US 2014/0115847 describes a process with a compressor to form the head. U.S. Pat. No. 4,816,100 also describes a process where a heated forming die is pressed onto the tampon blank in order to shape the introductory end. The issue in these processes is that the head-shaping step takes too much time because the quality of the heat-shaping depends on the temperature of the heating element and the duration of the heat-sealing step. More specifically, the quality is improved if heat-shaping is performed at lower temperature and for a longer duration, thus lowering production speed.
The invention aims to provide an apparatus and method which ensures a fast, efficient, reliable and cleaner shaping of the introductory end of a tampon.
The present invention provides an apparatus for shaping the introductory end of a tampon, comprising:
According to the invention, the head-shaping station comprises an ultrasonic device.
The ultrasonic device emitting ultrasonic vibrations enables to increase the number of hits to the tampon introductory end, when comparing to a conventional heating press, during a same amount of time. In other words, for the same amount of time, a ultrasonic device enables to get more hits to the tampon head in comparison to a convention heating press, thus the introductory end will be better shaped. Also, a conventional heating press requires 5 or 6 moulds to hit the tampon introductory end enough times to obtain a proper shaping of the head, whereas with an ultrasonic device, it is possible to reduce this number of moulds. This enable to improve the production yield, since the tampons can move quicker to a following stage, e.g. the wrapping step, where the tampon is covered by a wrapper.
According to an embodiment, the ultrasonic device comprises at least one head-shaping sonotrode emitting ultrasonic vibrations at a frequency between 10 kHz and 70 kHz, preferably between 20 kHz and 50 kHz, preferably a frequency of 35 kHz.
According to an embodiment, the ultrasonic device comprises a first and a second head-shaping sonotrodes emitting ultrasonic vibrations at a frequency between 10 kHz and 70 kHz, preferably between 20 kHz and 50 kHz, preferably a frequency of 35 kHz.
According to an embodiment, the first and second head-shaping sonotrodes are aligned on an arcuate axis.
According to an embodiment, the head-shaping station comprises an actuation mechanism enabling the movement of the ultrasonic device closer or remoter to the support wheel and the tampon.
According to an embodiment, the apparatus comprises a pushing mechanism comprising a plate with at least one protruding peg to press against the trailing end of the tampon that is opposite to the introductory end.
According to an embodiment, the first and second head-shaping sonotrodes have different cross sectional profiles.
According to an embodiment, the head-shaping sonotrode has a cavity that is ogive shaped.
The invention also pertains to a method for shaping the introductory end of a tampon using the apparatus as described above, comprising the steps of:
According to the invention, the shaping of the introductory end of the tampon is done with an ultrasonic device.
According to an embodiment, the ultrasonic device comprises at least one head-shaping sonotrode emitting ultrasonic vibrations at a frequency between 10 kHz and 70 kHz, preferably between 20 kHz and 50 kHz, preferably a frequency of 35 kHz, during a lapse of time which is comprised between 0.1 and 1 s, preferably between 0.2 and 0.5 s.
According to an embodiment, the ultrasonic device comprises a first and a second head-shaping sonotrode emitting ultrasonic vibrations at a frequency between 10 kHz and 70 kHz, preferably between 20 kHz and 50 kHz, preferably a frequency of 35 kHz, during a lapse of time which is comprised between 0.1 and 1 s, preferably between 0.2 and 0.5 s, the tampon being shaped by the first head-shaping sonotrode then subsequently by the second head-shaping sonotrode.
According to an embodiment, the shaping of the introductory end of the tampon further comprises the sub-steps:
According to an embodiment, the shaping of the introductory end of the tampon further comprises the sub-steps:
According to an embodiment, the method further comprises the sub-steps:
All of these embodiments mentioned above can be taken individually or in combination.
Further embodiments are described below and in the claims.
The present invention concerns an improved apparatus for shaping the introductory end of a tampon, and a method using such apparatus, as well as the product manufactured by said method and apparatus.
Unless otherwise defined, all terms used in disclosing the invention, including technical and scientific terms, have the meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. By means of further guidance, term definitions are included to better appreciate the teaching of the present invention.
As used herein, the following terms have the following meanings:
“A”, “an”, and “the” as used herein refers to both singular and plural referents unless the context clearly dictates otherwise. By way of example, “a compartment” refers to one or more than one compartment.
“About” as used herein referring to a measurable value such as a parameter, an amount, a temporal duration, and the like, is meant to encompass variations of +/−20% or less, preferably +/−10% or less, more preferably +/−5% or less, even more preferably +/−1% or less, and still more preferably +/−0.1% or less of and from the specified value, in so far such variations are appropriate to perform in the disclosed invention. However, it is to be understood that the value to which the modifier “about” refers is itself also specifically disclosed.
“Comprise,” “comprising,” and “comprises” and “comprised of” as used herein are synonymous with “include”, “including”, “includes” or “contain”, “containing”, “contains” and are inclusive or open-ended terms that specifies the presence of what follows e.g. component and do not exclude or preclude the presence of additional, non-recited components, features, element, members, steps, known in the art or disclosed therein.
The term “emit ultrasonic vibrations” is equivalent to the term “apply ultrasonic vibrations to”.
The terms “form” and “shape” are equivalent and means the spatial form or contour of an element and “shaping” means imparting a particular form or shape to an element, in particular the introductory end of a tampon.
The term “introductory end” equivalent to the term “head” means the end of the tampon that is designed to be inserted first in a body cavity. It corresponds to the end that is opposite of the end that presents the withdrawal string.
The term “trailing end” equivalent to the term “rear” means the end of the tampon that is designed to be inserted last in a body cavity. It corresponds to the end of that tampon that presents the withdrawal string.
The term “carrying pipe” means a housing with a tubular design that has a hollow inner space, or cavity, in order to receive tampon within said hollow inner space. In other words the carrying pipe corresponds to a hollow elongated cylinder.
The terms “sonotrode” and “head-shaping sonotrode” are equivalent.
The term “convex crown area” or “convex dome apex” designates a surface shape where each single point on the surface of the summit can be connected with each other point on the surface of the summit by means of lines running within the summit.
The term “nonwoven web material” means a sheet material having a structure of individual fibers or threads which are interlaid, but not in a regular manner such as occurs with knitting or weaving processes. Nonwoven fabrics or webs have been formed from many processes such as for example, melt blowing processes, spun bonding processes, and bonded carded web processes.
The term “thermoplastic” is meant to describe a material that softens when exposed to heat and which substantially returns to its original condition when cooled to room temperature.
The term “rayon” refers to a manufactured regenerated cellulose fiber, made from purified cellulose. It has a smooth, soft surface, and is therefore very suitable to be used in a tampon.
The term “concurrently” or “essentially concurrently” refers to the simultaneous or overlapping occurrence or execution of two or more events or steps.
The recitation of numerical ranges by endpoints includes all numbers and fractions subsumed within that range, as well as the recited endpoints.
A process for making a tampon comprises several steps. For example, the process comprises a bonding step where a first web material, for example an absorbent material such as rayon, viscose or cotton is bonded with a second web material, for example a thermoplastic film or a nonwoven web material. The process also comprises a winding and sealing step where the first and second web materials are winded and sealed together to form a tampon pre-blank. The tampon pre-blank is then compressed in a press. The compressed tampon is then transferred to the head-shaping apparatus according to the invention where the introductory end of the tampon is shaped. The tampon is then conveyed to a wrapping station where it is covered by a wrapper. Of course, the process can comprise additional steps such as the deposit of a withdrawal string and its knotting; the steps can be in this order or in another. The focus of the present invention pertains to a method for shaping the head, or introductory end, of a tampon and the apparatus to implement such method.
The plate 120 is attached to an actuating mechanism 122 (illustrated
As illustrated here, the actuating mechanism 122 corresponds here to a crank mechanism combined with a rod. More specifically, the actuating mechanism 122 comprises an arm 124 that is fixed to the plate 120 through a reversible or permanent fixation. As illustrated here, the actuating mechanism 122 comprises a lever 126 which rotates in a back-and-forth motion F through the impulse of a shaft 128 that is rotated itself by a motor (not illustrated). The lever 126 is linked to the arm 124 so that said arm 124 also moves in a back-and-forth motion. The arm 124 being linked to the plate 120 also forces it to move in a back-and-forth reciprocate manner. The peg 118 being attached to the plate 120 also moves in the same back-and-forth movements as the plate 120. The invention is not limited to this embodiment and other means of actuation can be considered as long as they induce a back-and-forth motion.
Preferably, the peg 118 and the plate 120 moves in a linear back and forth motion. In an embodiment, the plate 120 is carried by a sliding base 130 (as illustrated in
The amplitude of the movement of the plate and peg is limited by the rotation of the lever 126, the length of the arm 124. In addition or alternatively, the railing 132 can comprise stop ends to define a limit to the railing or cam track and restrict the movement of the plate 120 and pegs 118.
As illustrated in
As explained above, the diameter of the peg is smaller than the diameter of the hollow carrying pipe 106 so that when the pegs 118 are in motion thanks to the actuating mechanism 122, they slide within the hollow space of the carrying pipe 106.
As explained above, the number of pegs 118 on the plate 120 corresponds to the number of functional head-shaping sonotrodes 116 present at the head-shaping station 108. In the example illustrated in
As recited hereinabove, each compressed tampon pre-blank is transferred from the press 102 to a hollow carrying pipe 106, specifically within the interior space of the carrying pipe 106. The support wheel 104 then rotates in a clockwise direction so that the compressed tampon pre-blank reaches the head-shaping station 108. At that point, the peg 118 slides within the hollow carrying pipe and pushes the compressed tampon 162 against the head-shaping sonotrode 116. Each head-shaping sonotrode 116 applies ultrasonic vibrations at a frequency between 10 kHz and 70 kHz, preferably between 20 kHz and 50 kHz, preferably 35 kHz, to the introductory end 172 of the tampon 162. The introductory end 172 of the tampon 162 is thereby shaped in a dome-like configuration in order to have a shape that is more comfortable to insert in a body cavity.
The tip, or extremity, 138 of the ogive-shaped cavity 136 can be round shaped so that the tampon can have a dome-shaped meaning a convex dome apex or convex crown area. The tip 138 of the cavity 136 corresponds to the central part of the cavity 136, or the point where the two branches 135 start to branch out as illustrated in
The first and second sonotrode 116a, 116b can have the same profile, or shape, and/or dimensions, to ensure that the introductory end 172 of the tampon 162 is identical.
Alternatively, the two sonotrodes 116 can have different profiles, or shapes, and/or dimensions so that the second sonotrode 116b can make a fine tuning of the introductory end. For example, the cavity of the second sonotrode 116b can have the same diameter d as the first sonotrode 116a but a smaller length L than the cavity of the first sonotrode 116a in order to shape only a part of the introductory end 172.
In the embodiment where the first and second sonotrode 116a,116b have different dimensions, the pegs 118 preferably have different dimensions so that a peg 118 is adapted to the specific length of the corresponding sonotrode 116. For example, if the second sonotrode 116b has a smaller length L than the first sonotrode 116a, than the first peg 118a will have a longer length than the second peg 118b to compensate this length gap. Alternatively, the first and second pegs 118a,118b can have the same length and the second sonotrode 116b can be slightly shifted towards the support wheel 104 and the carrying pipe 106 to compensate the length difference, or in other words, the second sonotrode 116b is slightly shifted in a direction that is orthogonal to the axis on which the sonotrodes are aligned.
According to an embodiment not illustrated, ribs can also be placed within the cavity in order to form additional grooves 176 on the tampon head.
Preferably, the ultrasonic device 110 also moves in a linear back-and-forth motion. In an embodiment, the ultrasonic device 110 is carried by a sliding base 140 (as illustrated in
The plate 142 is attached to an actuation mechanism 146 (illustrated in
A method for shaping the introductory end of a tampon 162 according to the invention comprises the following steps as illustrated in
The invention is not limited to the previous embodiment. For example, according to another embodiment which is not illustrated, each compressed tampon arranged in a carrying pipe 106, is transported up to the first sonotrode 116a location. The first peg 118a is moved by the actuating mechanism 122 and slides forth within the carrying pipe 106. The first peg 118a abuts against the compressed tampon 162, specifically the trailing end 168 of the tampon 162, and pushes said tampon 162 up against the first sonotrode 116a specifically within the cavity 136 of the sonotrode 116 which stays stationary at this point. The first sonotrode 116a applies ultrasonic vibrations to the tampon introductory end 172 at a frequency between 10 kHz and 70 kHz, preferably between 20 kHz and 50 kHz, preferably 35 kHz, during a lapse of time which is comprised between 0.1 and 1 s, preferably between 0.2 and 0.5 s, for example 0.3 s. The peg 118 and the sonotrode 116 then slide concurrently towards the plate 120 so that the sonotrode 116 can push the tampon 162 back to its previous position in the carrying pipe 106. In other words, the sonotrode 116 slides forth towards the support wheel 104 whereas the peg 118 slides back away from the support wheel 104. The sonotrode 116 then slides backwards to its stationary position. This embodiment enables that the tampon 162 does not need to have a protruding portion sticking out from the carrying pipe 106 before reaching the head-shaping station 108 thus limiting contamination risks.
After the tampon introductory end has been shaped by the first sonotrode 116a, the support wheel 104 rotates and the carrying pipe 106 and tampon 162 are transferred to the second sonotrode 116b location. The tampon 162 can undergo the same process steps as described above for both sonotrodes. Alternatively, the tampon 162 can undergo the process steps described in the first illustrated embodiment for the first sonotrode and the alternative process steps for the second sonotrode or vice versa.
After the tampon introductory end has been shaped by the second sonotrode 116b, the support wheel 104 rotates and the carrying pipe 106 and head-shaped tampon 162 are transferred to the pusher 134 location. As illustrated in
The support wheel 104 rotates and the carrying pipe 106 is transferred to a transfer device 160 location. The transfer device 160 corresponds to a device that can push or pull the tampon 162 out of the carrying pipe 106 onwards to the wrapping station where the tampon 162 is covered by a wrapper. In other words, the process comprises a step where the tampon 162 is ejected from the carrying pipe 106.
According to an embodiment, the apparatus 100 for shaping the introductory end 172 of a tampon 162 can comprise a carrying pipe 106 for holding the tampon 162, a support wheel 104 that carries a plurality of carrying pipes 106, the support wheel 104 comprising conveying means to transport each carrying pipe 106, and a head-shaping station 108 for shaping the introductory end 172 of the tampon 162 wherein the head-shaping station 108 comprises an ultrasonic device 110 as described herein and a heating press. The heating press here may comprise a limited number of moulds, such as 1, 2, 3 or 4 moulds, to hit the tampon introductory end enough times to obtain a proper shaping of the head. Similarly, the head-shaping station may comprise a unique head-shaping sonotrode 116 emitting ultrasonic vibrations as described herein. Such apparatus can be useful to lower fiber loss in tampons while maintaining adequate production speed.
Naturally, the method for shaping the introductory end of a tampon using such an apparatus 100, comprises the steps of placing a tampon 162 inside a carrying pipe 106, conveying said carrying pipe 106 and tampon 162 to a head-shaping station 108, shaping the introductory end 172 of the tampon 162, conveying said tampon 162 away from the head-shaping station 108 wherein the shaping of the introductory end 172 of the tampon 162 is done with an ultrasonic device 110 and with a heating press. Preferably, the introductory end 172 of the tampon 162 is first shaped by the head-shaping sonotrode 116a using the sub-steps as described herein, the carrying pipe 106 and tampon 162 are conveyed to the heating press, the introductory end 172 of the tampon 162 is then shaped by the heating press.
It is supposed that the present invention is not restricted to any form of realization described previously and that some modifications can be added to the presented example of fabrication without reappraisal of the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 21161054.8 | Mar 2021 | EP | regional |
