Shell structure particularly for ski boots

Abstract: Shell structure particularly usable to produce a ski boot, comprising at least two separate parts (2, 6) which can be selectively mutually joined and are composed of a first body (2) which embraces the metatarsal region (3) and the instep region (4) and of a second body (6) which embraces the region of the heel of the foot. The first and second bodies furthermore have, approximately at the ground resting region, guiding means constituted by complementary profiles defined on the two parts to stiffen the structure and telescopingly couple them.

Description: The present invention relates to a shell structure particularly for ski boots, as defined in the preamble of claim 1 and as shown in FR-A-2 358 117. Ski boots are currently usually composed of elements, such as the shell and the quarters, obtained by injection-molding thermoplastic material. In particular, the manufacture of the shells requires the intervention of personnel after the molding has been performed in order to remove said shells from the mold. Furthermore this opeation must be immediate, since the shell has a structure which defines a narrowing at the foot instep, so that it is necessary to make use of the elastic deformation of said structure while it is still warm in order to remove it. For this purpose machines are used having programmed motions, with the disadvantage of having to solve problems such as the centering of said machines with respect to the mold and the centering of said machines with respect to the mold and the presetting of the machine's motions on three axes. Due to the semi-closed configuration of the shell, it is furthermore necessary to use personnel to assemble its internal components, constituted by pressers, mechanical elements connectable to levers, and others. Another disadvantage for the industrialization of ski boots resides in the fact that it is necessary to prepare a mold for each size in the range, increasing overall costs and entailing the selection of the size range to be offered to the public. To this respect, the US patent no. 4,308,674 describes a monolithic front-entry ski boot composed of a shell, in which a soft inner shoe can be inserted, and of an element which is rearwardly associable with said shell and includes a quarter which embraces the rear part of the leg. The sole of the shell is furthermore rearwardly provided with a pocket-shaped seat for coupling to said element, the locking therebetween occurring by means of downwardly arranged screws. The purpose of this solution is to allow the user to easily vary the size of the boot as the foot grows, this being a problem particularly felt in children's boots. The French patent application no. 7622307 also describes a ski boot of this kind. The main disadvantage observed in said known boots resides in the fact that the coupling provided by means of the pocket-shaped seat does not ensure an axially oscillation-free coupling between said element and said shell. The element which can be rearwardly associated with the shell furthermore has a quarter which cannot be used for the entire range as it is a characterizing part of the boot. Finally, the coupling region is furthermore visible, making the boot aesthetically unpleasant. The fact is also stressed that the hypothetical size change cannot be achieved directly by the customer and cannot be univocally preset by the manufacturer. The aim of the present invention is therefore to eliminate the disadvantage described above in known types by providing a shell which has optimum industrialization both during production and during assembly. Within the scope of the above described aim, an important object is to provide a shell which allows to easily automate its production and/or assembly steps. Another object is to provide a shell in which it is possible to achieve a considerable increase in production for an equal number of executable moldings. Yet another object is to provide a shell in which the same components can be used during assembly to obtain different sizes which cannot be modified by the user. Not least object is to provide a shell which is structurally simple, reduces industrialization costs and can be produced with conventional systems and known machines. The above described aim and objects, as well as others which will become apparent hereinafter, are achieved by a shell structure, particularly for ski boots, according to calim 1. Further characteristics and advantages of the invention will become apparent from the detailed description of a particular but not exclusive embodiment, illustrated only by way of non-limitative example in the accompanying drawings, wherein: figure 1 is a side view of the structure; figure 2 is a front isometric view of the second body; figure 3 is a rear isometric view of the first body; figure 4 is a view of the production of two units of the second body during a single molding process. With reference to the above described figures, the reference numeral 1 indicates a shell particularly usable for a ski boot, which is constituted by two separate parts which can be selectively joined to one another laterally and/or downwardly. Said shell 1 is therefore constituted by a first hollow body 2 affecting the metatarsal region 3 and the instep region 4. Said first body 2 furthermore has a rearwardly opening 5 for inserting the soft inner shoe and other components, such as a presser, cables and others, in said first body. Said opening 5 therefore facilitates and possibly automates the assembly of said components, since a possible operating head can operate on a horizontal plane by virtue of the direct access to the inside of the first body 2. A second body 6 furthermore co-operates to define the shell 1 and embraces the heel region 7. The second body 6 is also hollow to accommodate the heel region of the inner shoe which can be inserted at the opening 5 inside the first body 2. At its rear end, proximate to its lower surface 8, said first body 2 has a pair of longitudinal lateral grooves 9 for guiding complementarily shaped raised portions 10 which protrude inwardly from the lateral surfaces of said second body 6. Said grooves 9 and said raised portions 10 have the function of stiffening the structure, avoiding relative oscillatory motions of the two parts, and of facilitating the coupling between said first body 2 and said second body 6, ensuring their mutual centering; in this manner the lateral surfaces of the second body 6 embrace the corresponding ones of the first body 2, which thus arranges itself inside said second body 6. Said two bodies couple at the malleolar region 11 by virtue of high-frequency welding processes and/or mechanical coupling means such as for example rivets 12 or screws and/or glueing. A mechanical coupling may also be advantageously provided at the lower surface of the shell 1. The position of the possible rivets 12 may advantageously coincide with the articulation points of a possible quarter associable with the shell 1 thus obtained. The shell structure thus obtainable therefore has the advantage of allowing to separately manufacture the first body 2 and the second body 6, said bodies being very easy to remove from their molds even by virtue of preset mechanisms adapted to merely slip them off and not to twist them off, such as for example simple extractors. As illustrated in figure 4, it is furthermore possible to simultaneously mold two units of said body 2 using a T-shaped mold 13; an even higher productivity can be achieved with the body 6 due to the part's simplicity. This therefore allows a considerable increase in production for an equal number of executable moldings. The presence of the opening 5 at the second body 6 furthermore allows to facilitate and possibly automate the assembly of the internal components of the shell 1, since the head of the machine may work on a horizontal plane by virtue of said opening. As regards the adaptation of the shell to various sizes, it is sufficient to provide, during assembly, a different position for the connection of said first body 2 with said second body 6 before said bodies are coupled to one another. This allows, for example, to produce four elements of different dimensions constituting the first body 2 and two elements, also of different sizes, constituting said second body 6, to cover the range of eight sizes, thus considerably reducing the number of molds with considerable advantages in economy, management, production and organization. The lateral coupling proximate to the malleolar region between said first body 2 and said second body 6 achieves an aesthetic advantage since the coupling region is concealed by the quarter's lower edge. The fact is furthermore stressed that the second body 6 can be used for all the models in the range, further reducing the number of molds. The lateral coupling between the components of the shell 1 furthermore allows to pivot the quarters at said fixing points, so that for example in a rear-entry boot the front quarter may be pivoted to the front fixing point and the rear quarter may be pivoted to a point adjacent to the preceding one. In this manner the quarters follow the size variations of the shell, without varying the gap between the surfaces for the coupling of said shell and said quarter. It has thus been observed that the invention achieves the intended aim and objects, a shell having been provided which has optimum industrialization both during production and during assembly. Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such references signs do not have any limiting effect on the scope of each element identified by way of example by such reference signs.

Claims: Shell structure, particularly for ski boots, comprising at least one first body (2) adapted to embrace the metatarsal region (3) and at least one second body (6) adapted to embrace the heel (7) of the foot, said first and second bodies being separately obtained by molding and having guiding means (9,10) for their mutual telescoping coupling, various sizes of said shell structure being obtainable by means of said telescoping coupling, characterized in that said first body and said second body are rigidly coupled with one another, during the use of said shell structure, by virtue of coupling means (12) to provide said shell structure, said first body (2) extending from the metatarsal region upwardly therefrom so as also to embrace the foot instep (4), and said first and second bodies (2,6) being mutually rigidly coupled substantially at the malleolar region (11) of the shell structure. Structure according to claim 1, characterized in that said first body (2) has a hollow configuration which affects the metatarsal region (3) and the foot instep region (4) so as to rearwardly define an opening (5) adapted to allow the insertion of a soft shoe. Structure according to one or more of the preceding claims, characterized in that said second body (6) has a hollow configuration to accommodate the heel region (7) of a soft shoe. Structure according to one or more of the preceding claims, characterized in that said first body has, at its rear end, on its lateral surfaces, a pair of lateral guiding grooves (9) for complimentarily shaped protrusions (10) which protrude internally from the lateral surfaces of said second body. Structure according to claim 4, characterized in that said first body is partially arranged inside said second body once said bodies are assembled. Structure according to one or more of the preceding claims, characterized in that said coupling means comprise a plurality of rivets (12). Structure according to claim 6, characterized in that said rivets constitute the pivoting element for two separate quarters, one associable at said first body and the other associable at said second body.

Inventors: SARTOR MARIANO, SARTOR, MARIANO
Applicants: NORDICA SPA, NORDICA S.P.A.
Application year: 1989
Main classification: A43B5
IPC codes: A43B5, A43B3