NL2006215C2 - Saddle structure, particularly for pedal driven vehicles, and process for making such structure. - Google Patents

Description

“SADDLE STRUCTURE, PARTICULARLY FOR PEDAL DRIVEN VEHICLES, AND PROCESS FOR MAKING SUCH STRUCTURE”

FIELD OF THE INVENTION

5 This invention generally finds application in the art of pedal driven vehicles, and particularly relates to a saddle structure.

The invention further relates to a process for making such a structure.

STATE OF THE ART

10 Saddles for pedal driven vehicles, such as bicycles, tricycles or the like, are known to include a rigid support frame adapted to support a user’s body weight and to allow the saddle to be secured to the vehicle frame.

Compression at the contact points between the seat surface and the user is typically reduced by using elastic and/or shock absorbing elements, generally made of a 15 polymeric foam or a material having a viscous behavior, interposed between the seat surface and the rigid structure.

During the pedaling process, the inside thigh areas of the user repeatedly contact the side periphery of the saddle, and are continuously rubbed thereagainst, which causes local skin-rashes and grazes.

2 0 US-A-5,286,082 discloses a saddle which is able to pivot, by appropriate means, about the bicycle seat post, to accommodate movements of the rider’s body. While this arrangement increases comfort for the user, it still has certain well-known drawbacks.

The pivoting motion of the saddle may cause early wear of the mechanical parts for 2 5 connection to the seat post, and may lead them to fail with time. Furthermore, even though the outer portion of the saddle pivots, it is still in contact with the inside thigh areas of the rider, and still causes continuous rubbing of relevant surfaces, and consequent localized irritations. Also, these types of saddles have a very complex construction and require high manufacturing costs.

3 0 A saddle is further known from US-A-5,340,192, which has a support structure with a cavity for receiving a highly resilient elastic member therein. This structure also has certain known drawbacks.

2

First, the elastic member is placed outside the saddle structure, which increases complexity during both fixation and operation thereof. If the member is not properly secured to the base body, it can be displaced by the motion of the pedaling legs, thereby forcing the user to stop repeatedly to adjust its operation position.

5 Furthermore, the provision of an interposed secondary member adversely affects the appearance of the saddle and makes it aesthetically unpleasing. Finally, the use of and outside member requires the provision of a support frame, which will have to be more rigid and uncomfortable, especially at the inside thigh areas.

In an attempt to overcome these drawbacks, a number of solutions have been 10 developed, providing the use of supports having a different rigidity at the seating areas.

A saddle structure as described above is known from application W004/031025 by the Applicant hereof, which represents the preamble of claim 1. The differential rigidity of the support frame is obtained by using a plurality of elongate extensions, 15 outwardly projecting from respective peripheral recesses. These extensions are also interconnected by a member made of a plastic or elastomeric material.

While this solution allows to locally change the frame rigidity, it still has certain known drawbacks.

The material that forms the extensions is relatively rigid and poorly yielding under 2 0 compression stresses. Furthermore, the base material of the frame is elastically yielding by its nature and cannot permanently fit the user’s anatomy. In other words, the frame cannot be user-customized to optimize comfort during use.

AIM OF THE INVENTION

25 The technical aim of the present invention is to overcome the above drawbacks, by providing a saddle structure that achieves high efficiency and has a relatively simple construction.

Within such technical aim, an object of the present invention is to provide a saddle structure that can fit the pelvic conformation of any user.

30 A further object of the invention is to provide a shape-memory saddle structure, that can maintain the structural conformation taken under user induced compression stress. Another object of the invention is to provide a saddle stmcture that can increase user comfort, especially at the inside thigh areas.

3

Yet another object is to provide a cost-effective and easily-reproducible process for making a saddle structure.

This aim and these objects are reached by a saddle structure according to the attached claim 1.

5 Thanks to this particular arrangement, the saddle structure of the invention is able to fit any user’s body. The ability to permanently maintain a structural conformation that is optimized for user comfort, allows the structure to be customized to the specific needs of each user.

In a further aspect of the invention, a process is provided for making a saddle structure, 10 according to claim 18.

Further advantageous characteristics are described in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS These and further advantages will be better understood by any man skilled in the art from the description that follows and from the attached tables of drawings, given as a 15 non-limiting example, in which: figure 1 is a partly broken away perspective view of a saddle structure according to the invention; figure 2 is an axonometric view of a detail of figure 1; figure 3 is a bottom view of a detail of figure 1; 2 0 figure 4 shows a detail of figure 3, as taken in a partly broken away view, along a plane IY-IY; figure 5 is an axonometric view of the support frame of the saddle structure in another embodiment of the present invention; figure 6 is an axonometric view of the support frame of the saddle structure in yet 2 5 another embodiment of the present invention; figure 7 is a cross section of the support frame of the saddle structure according to the embodiments of figure 5 or 6, along a transversal plane; figure 8 is a cross section of the support frame of the saddle structure according to yet another embodiment of the present invention, along a transversal plane; 3 0 figure 9 is an axonometric view of the support frame of the saddle structure in another embodiment of the present invention; figure 10 is an axonometric view of the support frame of the saddle structure in yet another embodiment of the present invention; 4 figure 11 shows a flowchart of the process for making the saddle structure of the invention.

EMBODIMENTS OF THE INVENTION

Referring to the above figures, the saddle structure of the invention, generally denoted 5 by numeral 1, basically comprises a substantially rigid or semirigid support frame 2 and a yielding pad 3, for instance made of foam, secured to the upper face S of the frame 2. In a known manner, the structure has means 4 for connecting the frame 2 to a pedal driven vehicle, such as a bicycle, a tricycle or a tandem. For instance, these means 4 may consist of a housing having a cavity for a fork which connects the saddle to the 10 seat post of a bicycle frame.

A cover layer 5, which may be made of a soft synthetic material, such as lycra®, imitation leather or the like, is laid over the pad 3.

According to the invention, the frame 2 may have one or more differential deformability portions 6,6’,6”, which have a peculiar response to a compression stress. 15 To this end, the portions 6,6’,6” may consist of one fibrous membrane 7, which is selected of a type susceptible to deformation in response to a compression stress by a user, in such a manner as to change from a starting idle configuration to a final deformed configuration.

The base material of the membrane 7 will preferably be synthetic, and more preferably 2 0 selected from carbon, kevlar®, glass fibres or the like.

Conveniently, the membrane 7 may be incorporated in and closely joined to at least one layer 8 of an elastically yielding material, which is adapted to permanently and locally change the rigidity of the membrane 7 - layer 8 assembly by a structural change of the connection between the two materials, aimed at forming an integral shape memory 2 5 membrane.

Thus, the configuration of the frame 2 may be customized, i.e. adapted to the body of any user.

In practice, the portions 6,6’,6” will be made of a composite polymeric material, which provides a shape-memory structure in controlled conditions.

30 More in detail, the elastically yielding layers 8 may be joined to a predetermined number of fibrous membranes 7, so that the rigidity of the frame 2 may be progressively and not abruptly changed at the differential elasticity portions 6,6’,6”. A substantially uniform and continuous structure is thus obtained, which can effectively 5 support the user, while effectively reducing the stresses in the sensitive regions of the user’s body, and improving comfort of use.

Advantageously, each fibrous membrane 7 may be joined to at least one layer of elastically yielding material 8 by a resin, preferably a thermosetting epoxy resin.

5 As previously stated, the layer or the layers 8 is made of an elastically yielding material which is particularly similar to a natural or synthetic rubber, or mixtures of rubber and its derivates. In detail, it can be of a natural rubber, a synthetic rubber, a styrole rubber, a styrene-butadiene rubber, a poly-butadiene rubber, a nitryl rubber, a butylic rubber, a foam rubber and various mixtures of rubber or similar materials.

10 The operation of integral membranes in differential shape-memory portions 6,6’,6” may be summarized as follows: under external loads, the fibres that form the membrane 7 generate “microfractures” which permanently change the elastic structure, and take a configuration corresponding to the user’s anatomy, while keeping the typical elastic features of the polymer unchanged.

15 The elastically yielding layers 8 have two functions. In addition to imparting compliance to the assembly, they help to locally change the rigidity of the membrane 7 - layer 8 assembly, by virtue of the micro fractures at the interface between these two components, and within the assembly between the epoxy resin and the fibres of the membrane 7. This adds shape-memory properties to the structure, so that the latter may 2 0 fit the muscle conformation of any user.

Moreover, since the elastically yielding material of the layer or layers 8 - rubber or the like - has a substantially isotropic behaviour under stress, the assembly made by the combination of membrane 7 and layer 8 better fits to the muscle conformation and shape of the user.

25 In fact, the elastic deformability of the layer 8 in any loading direction allows the portions 6,6’,6” to fit to the muscles shape more accurately, so as to increase the comfort of the user during pedalling.

The portions 6,6’,6” are then softer to the contact of the user’s legs.

Furthermore, such portions 6,6’,6” are particularly yielding and flexible even if the 3 0 user’s position on the saddle changes during pedalling.

The construction of the frame 2 may include a laterally widened rear portion P for supporting the buttocks of a user and an elongate front portion A that defines a longitudinal axis X.

6

The portions 6,6’6” will be located in appropriate positions, coinciding with the parts of the user’s body mostly exposed to grazes and rubbing during the pedalling motion. Advantageously, at least one pair 6’ and 6” of these portions is located at the widened rear portion O and/or at the connection C between the elongate front portion A and the 5 widened rear portion P.

Conveniently, the pair of portions 6’ and 6” may be located at an outer peripheral edge 9 of the frame 2, symmetrically to the axis X, so as to form frame “wings”.

These wings will preserve the muscles of the inside thigh areas of the user, which will be in contact with portions specifically formed to accommodate the movements and be 10 readily deformed during use.

For the deformation to be maintained, the materials and the conformation of the support structure are both important. To this end, the frame 2 may have at least one recess 10’,10” along the edges 9. Also, the frame 2 may have at least one stepped profile 11 formed all along the same edge 9.

15 Thanks to this particular arrangement, the compression stress will not be concentrated in one point but can be transferred along the stepped profile 11, and will be transformed into a pulling stress exerted all over the structure, and progressively on the portions 6’,6”.

Advantageously, at least one of the differently deformable portions 6 may be located at 2 0 the elongate front portion A and/or at the connection C between the elongate front portion A and the widener rear portion P.

The portion 6 may conveniently have an elongate shape, with an axis of symmetry coinciding with the longitudinal axis X.

By this arrangement, the sensitive areas of the user’s pelvis may be protected, and any 2 5 local pain is thus prevented.

Another embodiment of the saddle structure according to the present invention is shown in figure 5.

The saddle structure 1 according to the present embodiment is identical to the one previously described, except for the fact that the membrane 7 comprises a plurality of 3 0 notches 12 along it external surface.

As shown in figure 5, such notches 12 are preferably, but not exclusively, concentrated along the deformable portions 6,6’,6”, and in particular along the edges of such portions 6,6’6”.

7

In other embodiments, the notches 12 could be distributed substantially along the whole surface of the membrane 7.

The notches 12 are deep enough in order to define respective lines of fracture of the membrane 7 under stress, in other words under user’s weight.

5 The fracture of the membrane 7 along one or more notches 12 causes the transition of the respective deformable portions 6,6’6” from a starting idle configuration to a final deformed configuration, as previously described. The deformed portions 6,6’6”, thanks to the presence of the layer 8 of elastically yielding material, are then particularly soft and comfortable.

10 The notches 12 are arranged substantially parallel - particularly in portions 6’,6” - or concentric - particularly in portion 6 - in order to define different lines of fracture according to the different conformations of the user’s pelvic region.

Figure 7 shows a cross section of the support frame 2 of the saddle structure of the present embodiment of the invention.

15 As shown in figure 7, the notches 12 may have a substantially triangular-shaped cross section, or any other cross section shape suitable to define a line of fracture under a certain weight.

Another embodiment of the saddle structure according to the present invention in shown in figure 6.

2 0 The saddle structure 1 according to the present embodiment is identical to the one of figure 5,7 except for the fact that each of the notches 12 is suitably interrupted in order to define a plurality of points of fracture.

In this embodiment, the deformation of the portions 6,6’,6” is achieved with a higher stress, in other words with a higher weight of the user, which is necessary to break the 25 membrane 7 along an interrupted notch 12 instead of a continuous notch 12 as in the previous embodiment.

Accordingly, in this embodiment the portions 6,6’,6” are less deformable than in the previous one.

It is pointed out that figure 7 shows a cross section also of the saddle structure 3 0 according to the embodiment of figure 6 when taken along a plain passing through the notches 12.

Another embodiment of the saddle structure according to the present invention in shown in figure 8.

8

This embodiment is identical to those of figures 5,6,7, except for the fact that the notches 12 - continuous or interrupted - are realized along the internal surface of the membrane 7.

This solution achieves a different behaviour of the membrane 7 under the user’s 5 weight.

For instance, in some cases this solution could achieve an easier and faster fracture of the membrane 7 under stress along the notches 12, since the stressed fibres of the membrane 7 could be those corresponding to its lower surface.

In other embodiments, not shown in the figures, the notches 12 may be provided along 10 both the external and the internal surface of the membrane 7.

Another embodiment of the saddle structure according to the present invention in shown in figure 9.

In this embodiment, the notches 12 are substantially incident in respect to the edges of the deformable portions 6,6’6”.

15 This solution achieves an even greater adaptability of the deformable portions 6,6’6” to the different conformations of the user’s pelvic region. In fact, with this arrangement of the notches 12, it is possible to obtain multiple fractures along each deformable portion 6,6’,6”.

Another embodiment of the saddle structure according to the present invention is 2 0 shown in figure 10.

The saddle structure 1 according to the present embodiment is identical to the one of figure 9 except for the fact that each of the notches 12 is suitably interrupted in order to define a plurality of points of fracture.

In this embodiment, the deformation of the portions 6,6’,6” is achieved with a higher 2 5 stress, in other words with a higher weight of the user, which is necessary to break the membrane 7 along an interrupted notch 12 instead of a continuous notch 12 as in the embodiment of figure 9.

Accordingly, in this embodiment the portions 6,6’,6” are less deformable than in the previous one.

3 0 A process for making the saddle structure as described above includes the following steps, which are schematically represented in the flowchart of figure 11.

In a first step a), a mould is set up, which has an internal cavity of a predetermined shape. In step b), the mould is opened and one or more layers 8 of an elastically 9 yielding material are deposited therein.

A step c) follows, in which one or more membranes 7 are set up, which are susceptible to deformation in response to an external compression stress to take a deformed configuration. Each membrane is then subjected to a step d) of impregnation with a 5 thermosetting resin.

Then, a step e) is carried out, in which one or more previously processed membranes 7 are laid over each layer of elastically yielding material 8, to define one or more portions 6,6’,6” having a different deformability from that of the rest of the frame 2.

In the next step f), the mould is closed and heated to a predetermined temperature, 10 preferably close to the glass transition temperature of the thermosetting resin. This temperature may be of 60°C to 180°C, and preferably of about 130°C .

After the step g) in which the mould is cooled to a final predetermined temperature, in step h), the mould is opened and the finished frame 2 is removed therefrom.

The next steps are step i) in which a yielding pad 3 is secured to the upper surface S of 15 the frame and step j) in which a cover layer 5 is laid thereon, to obtain the finished saddle.

Advantageously, step e) may be followed by a step e’) in which the fibres of the layer 8 and/or the membrane 7 are cut to break their continuity and facilitate the deformation of the membrane under stress.

2 0 From the above disclosure, the structure of the invention proves to fulfil the proposed objects and particularly meets the requirement of always fitting to the pelvic conformation of the user during operation.

The use of a composite material obtained by joining together a suitable number of layers 7 and 8, allows to form differently deformable portions of the frame 2, which are 2 5 able to “memorize” such deformation in time.

The structure of the invention is susceptible of a number of changes and variants, within the inventive concept disclosed in the appended claims. All the details thereof may be replaced by other technically equivalent parts, and the materials may vary depending on different needs, without departure from the scope of the invention.

3 0 While the structure has been described with particular reference to the accompanying figures, the numerals referred to in the disclosure and claims are only used for the sake of a better intelligibility of the invention and shall not be intended to limit the claimed scope in any manner.

Claims (21)

A saddle construction with shape memory, in particular for pedal-driven vehicles, comprising a substantially rigid or semi-rigid support frame (2), a resilient cushion (3) attached to the upper surface (S) of the frame (2) , a cover layer (5) laid over the yielding cushion (3), the frame (2) having one or more parts (6, 6 ', 6 ”) with a different formability with respect to the rest of the frame (2) ), characterized in that the differently deformable portions (6, 6 ', 6 ”) comprise at least one membrane (7) of fiber material that has a predetermined starting configuration, the fiber material being subject to deformation in response to a force exerted by a user so as to assume a final deformed configuration, the membrane (7) being closely connected to at least one layer of elastically yielding material (8) arranged to elastically secure the membrane (7) to keep on the body shape of the user. A structure according to claim 1, wherein the elastically yielding material is selected from natural rubber, a synthetic rubber, a styrene rubber, a styrene-butadiene rubber, a polybutadiene rubber, a nitryl rubber, a butyl rubber, 2. a foam rubber and various mixtures of rubber or similar materials. A structure according to claim 1 or 2, wherein the membrane (7) comprises a plurality of notches (12) suitable for defining respective fault lines or points. 25 Construction according to the preceding claim, wherein the notches (12) are provided along the outer and / or inner surface of the membrane (12). Construction according to the preceding claim, wherein the notches (12) are continuous. The structure of the preceding claim, wherein the notches (12) are interrupted. The structure of any one of the preceding claims, wherein the notches (12) substantially coincide with respect to the edges of the deformable portions (6, 6 ", 6"). 5 A construction according to any of claims 1-6, wherein the notches (12) are arranged substantially along the edges of the deformable portions (6, 6 ", 6"). A construction according to any one of the preceding claims, wherein the at least one membrane of fiber material (7) is connected by means of a layer of resin to the at least one layer of elastic yielding material (8). 10. Construction according to the preceding claim, wherein the resin is an epoxy resin. The structure of any one of claims 1-9, wherein the resin is a thermosetting resin. 2 0 The structure of any one of the preceding claims, wherein the fiber material of the at least one membrane (7) is a synthetic or natural material. A construction according to the preceding claim, wherein the synthetic or 2. natural material is selected from carbon, glass fiber or the like. A structure according to any one of the preceding claims, wherein the frame (2) has a laterally enlarged rear portion (P) for supporting a user's seat and an elongated front portion (A) defining a longitudinal axis (X). A construction according to the preceding claim, wherein at least one pair of differently deformable portions (6, 6 ', 6 ”) is located in the vicinity of the widened rear portion (P) and / or at the transition (C) between the elongated front portion (A) and the widened rear part (P). A construction according to the preceding claim, wherein at least one pair of differently deformable portions (6 ", 6") is provided on an outer peripheral edge (9) of the frame (2), symmetrical with respect to the longitudinal axis (X). The structure according to the preceding claim, wherein the frame (2) has at least one recess (10 ", 10") along the peripheral edge (9). 10 A structure according to claim 16 or 17, wherein the frame (2) has at least one stepped profile (11) along the peripheral edge (9). 19. Construction as claimed in any of the claims 14-18, wherein at least one of the sections (6) is located in the elongated front section (A) and / or in the transition (C) between the elongated front section (A) and the widened rear section (P). A construction according to the preceding claim, wherein the at least one differently deformable portion (6) is provided in the elongated front portion (A) and has an elongated shape, with the longitudinal axis (X). Process for making a shape memory saddle construction for vehicles as defined in one or more of the preceding claims, characterized in that it comprises the steps of: a) arranging a mold that has one internal cavity of a predetermined has a certain shape; b) opening the mold and applying at least one layer of elastic resilient material (8) therein; C) arranging at least one membrane (7) subject to elastic deformation in response to an external compressive force to assume a deformed configuration; d) impregnating the membrane (7) with a thermosetting resin; e) laying the at least one membrane (7) on the at least one layer of elastic resilient material (8), to define one or more portions (6, 6 ', 6 ") that have different formability with respect to from the rest of the frame (2); F) closing the mold and heating it to a predetermined temperature; g) cooling the mold to a predetermined final temperature; h) opening the mold and removing the finished frame (2) therefrom; i) attaching a resilient pad (3) to the top surface (S) of the frame (2); J) laying a cover layer (5) on the cushion (3).