Patent Application
20120144703
The invention relates to a method for producing a shell part of a sports shoe, in particular the front foot shell of a ski shoe, as well as a shell part of a sports shoe produced according this method, as described in claims 1 and 16. The invention also relates to a sports shoe, in particular a ski shoe, with a shell part produced or designed accordingly, as described in claims 31 and 32.
It is known from the prior art to construct such a shell part from several components preferably made of different materials, in order to obtain a shell part with high rigidity or stability. In this case in several injection molding processes respectively an additional injection molding component is added to a semi-finished product or the already existing part of the shell part. It is also known, to integrate in an injection molding process at least one additional, prefabricated component into the shell part, which component was not produced in particular by injection molding. The difficulties consist of developing the individual injection molding processes and the components to be integrated such that a simple and easily controllable production of the shell part of a sports shoe is made possible, which at the same time has a high degree of rigidity or stability.
GB 1 491 634 shows an outer shell part of a sports shoe produced in an injection molding process and a method for producing the shell part. To increase the tensile stiffness and rigidity of the elastic injection molding material of the shell parts in addition a porous, material-like insertion element is integrated into the shell part, whereby the injection molding material should penetrate and surround the insert element. The porous insert element consists of several layers of plastic fabric or plastic film and is placed precisely in those areas of the sports shoe, in which an increased rigidity and inflexibility is necessary or provided. According to the shown method on a foot-shaped last firstly the porous, material-like insertion element is raised, then the outer injection molding form is positioned over the last and lastly the injection molding material, such as for example polyurethane, is inserted into the space between the last and injection molding form. In this case the injection molding material is intended not only to penetrate the porous insertion element but also to lift slightly from the last, so that the insertion element is surrounded completely by the injection molding material and a uniform shell part is formed. Mainly the slight lifting of the insert element from the foot-like last is a method step which can only be controlled with difficulty so that it cannot always be ensured that the insert element is surrounded completely by the injection molding material. Thus it is completely possible that the insert element can be seen at least partly on the inner side or outer side of the shell part.
From EP 0 808 708 A1 an injection molding method is known in particular for shell parts of a sports shoe, in which firstly a soft injection molding material is inserted into the injection mold, so that channels are formed in the produced injection molding part. In a second method step said channels and similarly the adjoining areas of the injection molding part consisting of the soft material are overmolded with an inflexible injection molding material, in order to increase the stability or rigidity of the sports shoe. By means of overmolding beyond the area of the channels the escape of inflexible injection molding material is prevented at the upper edges of the channels in the second production step, as the injection molding form no longer has to be positioned exactly in a sealing manner at the upper edges of the channels, but reaches slightly outside the channels flat on the injection molding part made of soft material. In this way greater tolerances for the positioning or dimensions of the injection molding forms or injection molding parts are possible, whereby fewer reject parts are expected. The maximum possible rigidity of the shell part is however significantly limited by the exclusive use of injection molding materials in the production process.
The underlying objective of the present invention is to create a method for producing a shell part of a sports shoe, in particular the front foot shell of a ski shoe, which on the one hand enables a simple and easily controllable production of shell parts with very high rigidity or stability at least in specific areas and at the same time ensures the processability or adjustability of said shell part during production and in specific applications also afterwards. Furthermore, an objective of the invention is to create a shell part of a sports shoe, by means of which the said objectives can be achieved.
The first objective of the invention is achieved by means of a method according to claim 1.
According to the invention in the method for the shell part consisting of several components at least one three-dimensional, dimensionally stable shoe reinforcing part is used. On the inner side of the three-dimensional, dimensionally stable shoe reinforcing part a filler material which can be processed or worked comparatively easily compared to the shoe reinforcing part is applied, the three-dimensional inner side facing away from the shoe reinforcing part follows largely the form of a foot or inner shoe-shaped last, onto which the shoe reinforcing part provided with the filler material is attached or positioned in a following step. A last is defined as an element which models at least partly the inner chamber of a shoe to be produced and during the production of the shoe is used in particular for holding, fixing or shaping the shoe or its components. In particular, this includes a last used as an injection molding form for delimiting the inner chamber of a shoe to be produced. It is expedient if the workable filler material is applied onto at least 50%, in particular more than 75%, preferably 90% to 100 of the inner surface of the shoe reinforcing part. During the subsequent overmolding of the last with plastic also the shoe reinforcing part is overmolded at least partly and a one-piece shell part of a sports shoe is formed. The inner side of the shell part therefore consists on the one hand of a plastic and on the other hand of filler material applied onto the shoe reinforcing part. Said materials can be worked or processed easily and can thus be changed in a simple manner into different shapes, so that for example the inner side of the shell part can be adjusted to the actual requirements. It is also possible by varying the type of filler material and plastic to determine the properties of the shell part, for example its hardness. Thus by means of the method according to the invention a shell part is created, in which its inner side can be changed into different shapes and according to the given application can be provided with different damping properties, contours or surface and the like.
It is essential that the rigidity or stability lacking in the filler material and the plastic is provided by means of the three-dimensional, dimensionally stable shoe reinforcing part. The shoe reinforcing part is in this case applied in the shell part in a position, in which increased rigidity or stability is necessary. The problem of poor or difficult workability of the dimensionally stable shoe reinforcing parts is achieved in that the comparatively easily worked filler material is applied on its inner side. By way of the method according to the invention it is possible to combine the advantages of simple processability and adjustability with high rigidity or stability. In principle, the production of a shell part of a sports shoe by means of injection molding processes has not changed in essence.
Also the further measures according to claim 2 are advantageous, as in this way a form-bonded and thereby stable and robust connection is provided between the shoe reinforcing part and plastic part. By means of an at least partial overmolding of the outer side of the shoe reinforcing part in addition to improved form bonding it is also achieved that the advantages of plastic can be exploited for example in relation to the workability or damping properties at least partly on the outside of the shoe reinforcing part.
Also the measures of claim 3 are advantageous, as said materials are very stable or bending resistant and thus can be used to produce very high quality shoe reinforcing parts. Likewise the production and working processes of said materials are technically established nowadays.
Also the embodiment according to claim 4 is advantageous, as in this way shoe reinforcing parts can be created, which on the one hand have the necessary stability or rigidity and on the other hand are not too thick or too heavy to be accommodated in the shell part of a sports shoe.
The measures according to claim 5 are also advantageous, as in this way openings are formed in the dimensionally stable area of the shell part. If for example an axis which connects a first shell part to a second shell part, is guided through said opening, on the one hand said axis is mounted in a stable manner and on the other hand also an excellent and direct transfer of force from the axis to the shoe reinforcing element is ensured.
The embodiment according to claim 6 is also advantageous, as in this way improved form bonding is obtained between the shoe reinforcing part and plastic part, whereby the stability of the connection is increased.
By means of the advantageous measures according to claim 7 the form closure between the shoe reinforcing part and plastic part is improved further, so that the connection is even more resistant to stresses. The sliding of the connecting elements out of the enclosure of plastic is thus almost impossible.
The measures according to claim 8 are also advantageous, as in this way the quality of the form closure between the shoe reinforcing part and plastic part is improved even further.
The measures according to claim 9 are also advantageous, as in this way at several points of the shell part an increase in the rigidity or stability is achieved. Thus the shell part can be influenced very specifically in its bending resistance at those points at which an increased rigidity or stability is desired or where on the basis of the forces occurring in or on the shell part such a reinforcement is necessary.
In the measures according to claim 10 it is an advantage that the shell part of the shoe reinforcing part is reinforced exactly in those areas in which in very many cases an increased stability or rigidity is required. If for example the sports shoe, for which a shell part according to the invention is produced, is a ski shoe, an increased stability of the shell part is required mainly in the region of the heel and in the area of the front foot. This applies exactly to those areas in which in ski shoe sole extensions are formed, which enter into a form-bonded connection with a binding device. An increased rigidity or stability in these areas is an advantage, as in this way a more direct and undelayed transfer of force is ensured, as in these areas very high forces can occur. A further area in which it is very advantageous to position a shoe reinforcing part is in the sole area of a sports shoe. By placing a shoe reinforcing part in this area the bending or torsion rigidity of the sports shoes is increased, which for example in a ski shoe allows a more rapid or more aggressive movement.
The measures according to claim 11 are also advantageous, as said materials are lightweight and can be worked easily and can be changed into different, three-dimensional shapes. By using the different materials or by varying the material parameters of the respective material filler materials with very different properties can be used. In particular, the hardness of the filler material can be adjusted easily to the respective requirements.
The measures according to claim 12 are also advantageous, as in this way the thickness of the shoe reinforcing part with the applied filler material corresponds approximately to the thickness of the plastic part, which surrounds the shoe reinforcing part. Thus the shoe reinforcing part with the applied filler material and the adjoining plastic part form a one-piece shell part, which does not have abrupt, step-like transitions on its inner side.
The measures according to claim 13 are also advantageous, as in this way a shell part is formed in which mainly the inner side can be processed or adjusted very easily. In this case the highly stable shoe reinforcing part does not need to be processed, but only the filler material which is comparatively easily to work compared to the shoe reinforcing part.
Also an embodiment according to claim 14 is an advantage as in this way filler material is formed, the three-dimensional form of which, in particular the form of the inner side of the filler material facing away from the shoe reinforcing part, the material properties of which, in particular the hardness of the filler material and/or its haptic can be adjusted exactly and individually to the requirements or wishes of a user. Such an adjustment is possible in a simple manner, as the filler material can be very easily processed compared to the shoe reinforcing part.
Also the measures according to claim 15 are advantageous, as in this way it is possible that the three dimensional inner side of the filler material facing away from the shoe reinforcing part and thus at least one part of the inner side of the shell part can be adjusted in its shape and/or haptic subsequently and individually to the specific requirements or wishes of a user of the sports shoe or the filler material can be post-processed accordingly. Such a wish may come for example from people with special foot shapes or people with ganglions on their feet. Now it is possible in a simple manner to respond to special wishes or requirements, without affecting the stability or rigidity of the shell part, as the shoe reinforcing parts are not processed.
The objective of the invention, in particular the second said objective of the invention is achieved independently also by a shell part of a sports shoe according to claims 16 to 30. Likewise the objective of the invention is achieved by a sports shoe according to claims 31 and 32.
The technical effects or advantages achieved by the measures according to claims 16 to 32 can be taken from the preceding parts of the description, in particular the defined advantages of the corresponding claims 1 to 15.
For a better understanding of the invention the latter is explained in more detail with reference to the following Figures.
In a much simplified schematic view:
First of all, it should be noted that in the variously described exemplary embodiments the same parts have been given the same reference numerals and the same component names, whereby the disclosures contained throughout the entire description can be applied to the same parts with the same reference numerals and same component names. Also details relating to position used in the description, such as e.g. top, bottom, side etc. relate to the currently described and represented figure and in case of a change in position should be adjusted to the new position. Furthermore, also individual features or combinations of features from the various exemplary embodiments shown and described can represent in themselves independent or inventive solutions.
All of the details relating to value ranges in the present description are defined such that the latter include any and all part ranges, e.g. a range of 1 to 10 means that all part ranges, starting from the lower limit of 1 to the upper limit 10 are included, i.e. the whole part range beginning with a lower limit of 1 or above and ending at an upper limit of 10 or less, e.g. 1 to 1.7, or 3.2 to 8.1 or 5.5 to 10.
The method according to the invention for producing a shell part 1 of a sports shoe, in particular the front foot shell of a ski shoe, is based on joining together several components of the shell part 1 made preferably from various different materials in one or more injection molding process. It is essential in this case that in a first step at least one three-dimensional, dimensionally stable shoe reinforcing part 2 is produced. The produced shoe reinforcing part 2 gives the finished shell part 1 of a sports shoe in its heel area 4 a high degree of stability or bending resistance. Owing to the use of highly stable materials for the shoe reinforcing part 2 the processing or adjustment of said part is relatively difficult or complex. For this reason in a subsequent method step a filler material which is comparatively easy to work is applied onto the inner side of the shoe reinforcing part. The filler material 3 is shaped in this case so that the three-dimensional, inner side 10 of the filler material 3 facing away from the shoe reinforcing part 2 largely follows the shape of the last 7.
It is advantageous if the filler material 3 which is comparatively easy to work is applied onto at least 50%, in particular more than 75%, preferably 90% to 100% of the inner surface 9 of the shoe reinforcing part 2. By applying the filler material 3 onto the inner side 9 of the shoe reinforcing part a composite part is formed, the inner side 10 of which can be worked or adjusted comparatively easily. Thus a composite part is formed which has a high degree of rigidity and also good workability. In a subsequent step of the method according to the invention the shoe reinforcing part 2 provided with filler material 3 is applied or positioned in the heel area 4 of the last 7. This is possible without any difficulty, as the filler material 3 applied onto the inner side 9 of the shoe reinforcing part has an inner side 10, the three-dimensional shape of which is adjusted largely to the form of the last 7. In a final method step the still free area of the strip 7 is overmolded with a plastic, so that a plastic part 8 is formed, which also at least partly surrounds the dimensionally stable shoe reinforcing part 2 and thus forms a one-piece shell part 1 of a sports shoe. The arrangement of the components shoe reinforcing part 2, filler material 3 and plastic part 8 is illustrated particularly clearly in the cross sectional views in
According to an advantageous embodiment the edge section 11 of the shoe reinforcing part 2 is overmolded at least partly with plastic, so that a one-piece shell part 1 of a sports shoe is formed, in which the components shoe reinforcing part 2 and plastic part 8 are joined together in a reliable and form-bonded manner. According to a not shown exemplary embodiment the plastic part 8 also surrounds at least part of the outer side 12 of the shoe reinforcing part 2, whereby furthermore an even more resistant form-bonding is obtained between the components of the shell part 1.
The inner side 9 of the shoe reinforcing part 2 in the method according to the invention does not have to be largely overmolded with plastic, as said inner side 9 is covered to a large extent with filler material 3. Thus during the injection molding process for the production of the plastic part 8 it is no longer necessary to ensure that the plastic also reaches the whole intended area below the shoe reinforcing part 2. The method according to the invention simplifies in this way the production process of the shell part 1 of a sports shoe.
Preferably, the three-dimensional, dimensionally stable shoe reinforcing part 2 is made of metal or a fibrous composite material such as for example a carbon-fiber reinforced plastic, a glass-fiber reinforced plastic, a carbon and glass-fiber reinforced plastic, and aramid fiber composite material or a basalt fiber composite material. In principle, the processing of said highly stable materials is technically developed, however their processing or working is relatively costly compared to injection molded plastics.
It is advantageous, if the thickness of the three-dimensional, dimensionally stable shoe reinforcing part 2 is 0.6 mm to 1.5 mm, preferably 0.9 mm to 1.2 mm. The thus formed shoe reinforcing part 2 has on the one hand sufficient stability or rigidity and on the other hand its weight and dimensions are such that the shoe reinforcing part 2 can be integrated easily into the shell part 1 of a sports shoe.
According to a particularly advantageous embodiment, the three-dimensional, dimensionally stable shoe reinforcing part 2 comprises one or more, in particular round, openings 13 between the inner side (9) and outer side (12). Said openings 13 are not closed completely by either the filler material 3 or the plastic part 8. They are used for example for mounting an axial element which connects the shell part 1 to an additional shell part in a movable manner.
According to a particularly advantageous embodiment in the edge section 11 of the three-dimensional, dimensionally stable shoe reinforcing part 2 one or more connecting elements 14, 15 are formed. In the course of the method according to the invention during the overmolding of the shoe reinforcing part 2 said connecting elements 14, 15 are surrounded by the plastic part 8, so that a very stable and reliable connection is formed between the shoe reinforcing part 2 and the plastic part 8. During the overmolding of the shoe reinforcing part 2 with plastic a form and force-bonded connection is formed between the two components. Depending on the materials used for the shoe reinforcing part 2 and the plastic part 8 and the parameters of the injection molding process, for example the temperature of the molding material, similarly a material bonded connection is formed between the two components, in which said parts enter into a chemical bond. In particular, the cross sectional views in
In order to increase further the stability or resistance of the connection between the three-dimensional, dimensionally stable shoe reinforcing part 2 and the plastic part 8, it is advantageous to provide the connecting elements 14, 15 with openings 16. On overmolding the shoe reinforcing part 2 with plastic said openings 16 are filled with plastic and a more stable and reliable connection is formed between the shoe reinforcing part 2 and the plastic part 8. The cross sectional views in
A further expedient procedure for increasing the stability or resistance of the connection between the shoe reinforcing part 2 and plastic part 8 consists of completely overmolding the connecting elements 14, 15 both on their outer side 18 and also on their inner side 17 with plastic. In a shell part 1 for a sports shoe produced according to this method both sides 17, 18 of the connecting elements 14, 15 are connected to the plastic part 8 and are therefore connected in a reliable and stable manner. Said embodiment is shown in particular in the cross sectional views of
By means of increasing the width of the connecting elements 14, 15 during the overmolding with plastic a larger overlapping area is formed between the connecting elements 14, 15 and the plastic part 8, so that the stability of the connection between the shoe reinforcing part 2 and plastic part 8 is increased. Similarly it is advantageous to increase the robustness or stability of the connection between the shoe reinforcing part 2 and plastic part 8 by providing a cross member 19 for example on the connecting element 15, as shown in particular in the cross sectional view in
According to an advantageous embodiment a plurality of shoe reinforcing parts 2 provided with filler material are integrated into the shell part 1 of a sports shoe. In addition to the positioning of a shoe reinforcing part 2 shown in the exemplary embodiments in the heel area 4 or ankle area of the shell part 1 of a sports shoe, it is also advantageous to position a shoe reinforcing part 2 in the toe area 5 and/or in the sole area 6. In this way the rigidity and the bending and torsion resistance of the shell part 1 is increased in these areas. The thus produced shell part 1 of a sports shoe supports in this way the heel or ankle area, the front foot area and/or the foot sole area of a user of the sports shoe.
However, not only the bending resistance of the shell part 1 is increased, but the shell part 1 in the areas of the shoe reinforcing part 2 is also more robust to stresses or forces, which act externally on the shell part 1. The closeness of the shoe reinforcing part 2 or the connecting element 15 to the rear sole extension 20 of the shell part 1 also improves the force transmitting properties to a binding element, in which the shell part 1 can be inserted. In a not shown exemplary embodiment of a shoe reinforcing part 2 for the toe area 5 of a shell part 1 of a sports shoe it is also expedient to position in the region of a front sole extension 21 a shoe reinforcing part 2 for the toe area 5 or its corresponding connecting element 15.
Preferably, the filler material 3 which is comparatively easy to work compared to the shoe reinforcing part 2, which filler material is applied onto at least one part of the inner surface 9 of the shoe reinforcing part 2, is made of a plastic foam, such as for example foamed polystyrene, polyurethane-foam or polypropylene-foam. Said materials can be brought in a simple manner into various different shapes and by varying their material composition and their processing methods also their material properties can be adjusted, for example their hardness, so that in particular also the haptic of the filler material 3 can be adjusted to the requirements or wishes of a user of the sports shoe. According to an advantageous embodiment the filler material 3 which is comparatively easy to work has a thickness of 1 mm to 12 mm, preferably 2 mm to 7 mm. The resulting total thickness of the composite part consisting of a shoe reinforcing part 2 and filler material 3 applied on the inside in this way corresponds approximately to the thickness of the plastic part 8, so that a one-piece shell part 1 is formed with transitions running between the shoe reinforcing part 2 or the filler material 3 and the plastic part 8.
It is expedient, if the filler material 3 applied onto the inner surface 9 of the shoe reinforcing part 2 can be shaped, in particular easily milled, cut, rasped, ground and/or shaped after heating. This makes it possible on the one hand that in particular the inner side 10 of the filler material 3 during the production of the shell part 1 can be formed into the different three-dimensional shapes adjusted to the requirements of the user of the sports shoe and/or its haptic can be adjusted. It is thus also possible to subsequently adjust the three-dimensional shape of the filler material 3, in particular its inner side 10, and/or the haptic of the filler material 3 according to the special or individual requirements of a user of the sports shoe in a post finishing process. Such a wish may apply for example in people with special foot shapes or people who have ganglions on their feet. Prior to working the filler material 3 in an expedient manner a 3D measurement of the individual foot shape of the user of the sports shoe is performed.
For the production method of the shell part 1 it is also expedient to produce the dimensionally stable shoe reinforcing part 2 individually with regard to its dimensions for each shoe size of the sports shoes to be provided.
The exemplary embodiments show possible embodiment variants of the shell part of a sports shoe, whereby it should be noted at this point that the invention is not restricted to the embodiment variants shown in particular, but rather various different combinations of the individual embodiment variants are also possible and this variability, due to the teaching on technical procedure, lies within the ability of a person skilled in the art in this technical field. Thus all conceivable embodiment variants, which are made possible by combining individual details of the embodiment variants shown and described, are also covered by the scope of protection.
Finally, as a point of formality, it should be noted that for a better understanding of the structure of the shell part of a sports shoe, the latter and its components and have not been represented true to scale in part and/or have been enlarged and/or reduced in size.
The problem addressed by the independent solutions according to the invention can be taken from the description.
Mainly the individual embodiments shown in
| Number | Date | Country | Kind |
|---|---|---|---|
| A 1878/2010 | Nov 2010 | AT | national |
