Patent Application
20140093695
The invention relates to a method for the production of a padded layer arrangement for a padded body protection and relates to a padded layer arrangement according.
Padded layer arrangements of the type mentioned at the beginning are used for the production of padded body protection elements, such as those integrated in protective helmets or in functional sportswear. Here, the protective function is essentially based on absorbing blows or shocks by means of the shaped particle fillings that are formed in hollow bodies of the padded layer arrangement.
For attaining the best absorbing capacity possible, the aim is a packing density as high as possible of the shaped particles in the shaped particle package. This can be achieved, amongst other things, in that the hollow bodies are evacuated by means of an evacuation device and in that in this way, by means of the vacuum, a dense package is developed. Here, a dimensional stability is created at the same time such that, after the evacuation, the protective element has a mostly fixed shape, independently of the dimensional stability of the plastic casing.
The vacuum-related effect presumes that either valve devices suitable for a temporary evacuation have to be formed at the padded layer arrangement, or the padded layer arrangement is formed in a correspondingly complex manner, in the case of a permanent evacuation, in order to ensure that the vacuum is maintained for the lifespan of the padded layer arrangement.
Therefore, it is an object of the present invention to provide a padded layer arrangement for a body protection element which can both be easily handled and easily produced.
The present object is attained by a method according to the invention as well as by a padded layer arrangement according to the invention.
With the method according to the invention, initially a plurality of pocket-shaped protuberances is formed in the base layer. Here, it is irrelevant whether the base layer initially is a completely flat layer that is stiff in itself or whether it is present in the form of a flexible and untensioned structure. At the very least, in the first step, the corresponding reshaping for forming the protuberances is effected.
For filling the pocket-shaped protuberances, the elastic shaped particles are filled in as a loose bulk. The shaped particles can be deformed at least in an elastic or semi-elastic and elastic-plastic manner. For instance, plastic balls made of polystyrene or of a similar material can be used.
Subsequently, a cover layer is applied onto the base layer. In this case, in the area of filling openings, which have been developed beforehand as a result of the formation of the pocket-shaped protuberances, the cover layer covers the base layer such that the shaped particle fillings and the filling openings are surrounded.
Consecutively, a temperature is applied to the cover layer that is arranged on the base layer and a vacuum is applied to the hollow spaces. The vacuum formed in the hollow spaces results in a compression of the loose bulk of shaped particles that is present in the hollow spaces. In this way, the space occupied by the shaped particle filling is reduced. Simultaneously with compressing the shaped particle filling, a deep-drawing of the cover layer onto the shaped particle filling is effected. Corresponding to the deformation of the cover layer, projections that extend into the protuberance are developed. This means that, corresponding to the pocket-shaped protuberances, projections are formed that are smaller in each case as well as in the same orientation. Furthermore, at the same time or subsequently, a joining connection is created in a connection zone that is formed at the upper edge of the pocket-shaped protuberance between the base layer and the cover layer. In this case, a permanent connection between the base layer and the cover layer is developed. The joining connection can be formed in a gas-tight manner, depending on the configuration.
The method according to the invention makes it possible in a particularly easy and cost-effective manner to produce a padded layer arrangement which has the advantageous shock-absorbing features without requiring the formation of the vacuum within the hollow bodies. It is only required to generate a vacuum in the production process in order to achieve a high packing density of the shaped particle filling or even an elastic pre-tensioning of the shaped particle filling by reducing the size of the hollow body interior.
With respect to the connection of the cover layer to the base layer in the connection zone, the precise embodiment of the joining connection is initially irrelevant. In a particularly advantageous embodiment, the joining connection is, however, produced by circumferentially welding the base layer to the cover layer, wherein a substantially gas-tight connection between the base layer and the cover layer is created.
It is particularly advantageous if, for forming the pocket-shaped protuberances, the base layer is initially put to rest on a mold plate with pocket-shaped mold cavities. In this case, the base layer can be both an element that is stiff in itself and an unstable element. At least, the base layer, which has been heated to deformation temperature, is pulled down into the mold cavities owing to a vacuum applied in the same. In this case, it is initially irrelevant how the deformation temperature is generated. On the one hand, it is possible to preliminarily heat the base layer externally and to apply the same at the elevated temperature. It is, however, advantageous to heat the base layer after applying it onto the mold plate. This can be done before applying or simultaneously with applying the vacuum. In this case, the heating can be effected both by means of a contact heater and by means of a radiation heater.
It is particularly advantageous if the base layer is configured to be gas-tight. Then, it can be configured as a plastic film. In this way, it is made possible in a simple manner to apply the vacuum in the mold cavities, without additional auxiliary means being necessarily required.
Alternatively, it is also possible to use, as the base layer, a layer that is not gas-tight initially, for instance a textile synthetic structure. For enabling a reshaping by means of a vacuum, here, the base layer can be covered by an additional gas-tight layer. It is obvious that, in this case, the additional layer has to present the necessary thermal stability for reshaping the base layer and the necessary deformability for forming the pocket-shaped protuberances.
Additionally or alternatively to using a vacuum for forming the pocket-shaped protuberances from the base layer, there is also the possibility to generate an overpressure on the upper side of the base layer, that is, when using a vacuum, on the side of the base layer facing the vacuum. In this case, in a simple manner, compressed air can be used which, in a production site, is usually available more easily as an auxiliary means than a vacuum to be generated. It is self-evident that a substantially sealing casing above the base layer is required in order to be able to generate the advantageous overpressure. What is not required is a complete gas-tightness. Thus, for instance, an upper-side tool for heating the base layer can be configured in such a manner that an overpressure between said tool and the base layer can be generated above the mold cavities. The required reshaping of the base layer is effected due to the pressure difference between the pressure above the base layer and the pressure within the mold cavities below the base layer. Correspondingly, using a vacuum within the mold cavities results in a reshaping having the same effect as using an overpressure above the base layer.
When using a base layer that is not gas-tight, however, a deformation by means of a stamping tool is particularly suitable, wherein the base layer is pressed down into the corresponding mold cavities by a heated mold stamp.
It is particularly advantageous if, for forming the projections of the cover layer that extend into the protuberance, a vacuum is applied to the hollow spaces which are defined by the base layer being covered by the cover layer via a bottom opening that is formed in a bottom wall of the protuberance.
The type of the bottom opening is initially irrelevant. In the case of a base layer that is not gas-tight, said bottom opening is directly given due to the missing gas-tightness.
When using a gas-tight base layer, the bottom opening is formed in a particularly advantageous way by means of a perforation of the bottom wall that rests against the mold cavity bottom. In this case, in a particularly advantageous way, a tool is used which is inserted into the deaeration opening of the mold plate. In this respect, the perforation of the base layer is effected from the side of the mold plate through the deaeration opening while producing the bottom opening.
In this case, it is irrelevant whether the perforation is generated while the vacuum is applied in the deaeration opening or whether initially, the perforation is carried out and subsequently, the vacuum is applied. At least, in an advantageous way, the tool is inserted into the deaeration opening for the purpose of the perforation.
For producing the projections that extend into the protuberance by means of a vacuum, a gas-tight seal is required on the upper side. This is realized in a particularly advantageous way by a gas-tight cover layer. In this respect, the cover layer can also be selected to be a regular cost-effective thermoplastic film.
Alternatively, it is possible to select the cover layer to be a thermoplastically deformable layer, too, which is, however, not configured to be gas-tight. For generating the required gas-tightness, for the purpose of the vacuum application, the cover layer is advantageously covered from the rear by another gas-tight layer. In this case, the additional gas-tight layer is required to be flexible in order to enable the deformation starting from the non-deformed cover layer for forming the projections that extend thereinto.
In an advantageous way, the application of temperature to the cover layer or to the layer that covers the cover layer is effected by means of a contact heater. Here, in a first embodiment, the cover layer can be put to rest on a flat heated tool. After becoming soft, by means of the vacuum, the projections can be formed. It is also possible to adapt the type of tool selected for heating the cover layer to the formation of the projections. In this respect, those areas of the cover layer are initially heated which are primarily deformed. In this case, in an advantageous way, the heating can be carried out continuously while the cover layer is reshaped.
Alternatively to the contact heater, in a particularly advantageous way, the application of temperature to the cover layer or to the gas-tight layer that covers the cover layer can be effected by means of a radiation heater. Due to using a radiation heater, it is not required to produce another mold tool. Furthermore, this embodiment has particular advantages since, triggered by the vacuum, the heating of the cover layer by means of the radiation heater can unabatedly be carried out during the deformation process. In this case, the radiation heater can carry out a regular radiation of the entire surface of the cover layer with the most simple embodiment. However, it is particularly advantageous if the radiation heater provides a variably distributed radiation energy corresponding to the shapes and the distribution of the protuberances and thus, of the projections to be produced. In this respect, particularly the areas to be deformed can be heated, whereas areas that are not to be deformed are subjected to a smaller temperature load.
Furthermore, it is advantageous if, before or after, particularly advantageously during application of the vacuum, such a tool is used which simultaneously produces the joining connection between the base layer and the cover layer in the connection zone in the upper edge surrounding the pocket-shaped protuberances. In this regard, it is advantageous if the means for generating the heating of the cover layer can be used at the same time for producing the joining connection.
According to the invention, the padded layer arrangement comprises a plurality of hollow bodies, which are formed in a layer composite between a thermoplastically deformable base layer and a thermoplastically deformable cover layer and which have a body casing that is formed by a base layer area and by a cover layer area, which are connected to each other via a joining connection in a connection zone that is circumferential in the plane of the layer composite, said connection zone forming an upper edge of a pocket-shaped protuberance of the base layer area, wherein the body casing has a shaped particle filling consisting of a plurality of elastic shaped particles and, for compressing the shaped particle filling, in the cover layer area, a projection is formed that extends into the protuberance.
In principle, a plurality of hollow bodies is envisaged which are formed in a layer composite between a thermoplastically deformable base layer and a thermoplastically deformable cover layer. Although the padded layer arrangement could also simply comprise a single hollow body for attaining the advantages according to the invention, an embodiment with a plurality of hollow bodies is preferred.
An essential feature of the padded layer arrangement according to the invention is that, for compressing the shaped particle filling or the loose bulk of elastic shaped particles, the cover layer area is formed as a projection that extends into the protuberance.
The padded layer arrangement according to the invention is in particular characterized by the particularly simple manner of production, which includes that the projections are formed in the same orientation as the protuberances. Due to this embodiment, a particularly dense packing of the shaped particles can be achieved and thus, the best possible protection level is achieved without an application of an additional vacuum being additionally required, as is usual in the state of the art.
Furthermore, the padded layer arrangement is suitable to be used in a variety of fields of application. Thus, the padded layer arrangement can be used for very different purposes, for instance for body protection or for protection of items during transport. It is also possible, for an individual use, to deform the padded layer arrangement again in the area outside the hollow bodies by means of below-described process steps due to the thermoplastically deformable base and cover layers.
It is particularly advantageous if the body casing has an opening. In an advantageous way, the opening is formed as a bottom opening in a bottom wall of the pocket-shaped protuberance here. It is obvious that in this way, when using the padded layer arrangement in the hollow body, no vacuum is applied. Nonetheless, the padded layer arrangement has the particularly advantageous dense packing which is necessary for attaining a high protection level. However, due to the missing vacuum, a manual reshaping after a deformation is made possible by a shock-like load. On the other hand, in the state of the art, it is required to remove the vacuum and, after the reshaping, to generate the vacuum anew.
In one advantageous embodiment, the base layer and/or the cover layer are made of a thermoplastic material with a textile structure. In this respect, for the padded layer arrangement, the choice of materials can be planned on the basis of the subsequent use. Occasionally, applying an additional laminating upper layer can thus be omitted.
It is furthermore advantageous if the base layer and/or the cover layer are provided with at least one further cover layer. Thus, as a finished component, the padded layer arrangement can be provided with the necessary surface features for the individual use.
The padded body protection element or padded protection body according to the invention comprises a padded layer arrangement according to the invention.
In the following figures, one embodiment of a padded layer arrangement according to the invention, a method for the production thereof and an example of use are sketched by way of example. The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.
In the drawings:
Referring to the drawings in particular,
In the area of a bottom wall 15 of the pocket-shaped protuberance 07, a bottom opening 14 is arranged, which, with the finished padded layer arrangement 01, enables a ventilation of the hollow bodies 05 and—as explained in the following—a deaeration of the hollow bodies when the padded layer arrangement 01 is produced.
In the
Under the influence of an elevated temperature as well as by applying a vacuum 23 at the deaeration opening 22, a deep-drawing of the base layer 03 into the mold cavity 21 is effected, as illustrated in
Subsequently, the bottom opening 14 is formed in the bottom wall 15, as shown by
After filling the protuberance 07, as illustrated in
By applying a vacuum 23 at the deaeration opening 22, as illustrated in
The result of the method is the padded layer arrangement 01 illustrated in
After the production of the padded layer arrangement, in another reshaping process, the padded layer arrangement can be reshaped for generating a desired contour that is stable in shape, which means for instance a bowl-shaped contour.
In
While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2011 100 642.0 | May 2011 | DE | national |
This application is a United States National Phase Application of International Application PCT/DE2012/000418 filed Apr. 24, 2012 and claims the benefit of priority under 35 U.S.C. §119 of DE 10 2011 100 642.0 filed May 5, 2011, the entire contents of which are incorporated herein by reference.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/DE12/00418 | 4/24/2012 | WO | 00 | 11/4/2013 |
