WO1995011066A1

WO1995011066A1 - Device for decreasing the pressure of the ends of a ski on the snow according to the pressure exerted by the skier on the ski

Info

Publication number: WO1995011066A1
Application number: PCT/FR1994/001131
Authority: WO
Inventors: Philippe Commier; Jacques Le Masson
Original assignee: Salomon S.A.
Priority date: 1993-10-20
Filing date: 1994-09-28
Publication date: 1995-04-27
Also published as: FR2711321A1; FR2711321B1

Abstract

The invention relates to a ski intended particularly for downhill skiing, comprising a lower base plate (1) having its own thickness distribution and comprising a central portion (2) slightly cambered between two contact lines, respectively front (20) and back (21); said central portion comprises at least one front stiffener (5), and/or back stiffener (6), connected at one of the ends (50, 60) to the front of the central portion (2) or to the back of the central portion (2) respectively, the other end (51, 61) being situated in the bearing area (200) of the ski boot (9) and being connected to at least one intermediary linking means (7). Said means (7) is situated in said bearing zone and is directly or indirectly in contact with the boot so as to receive a vertical pushing force (P) from the boot in a downward direction; said means (7) being designed to transmit, at least partially, said pushing force, in the form of at least one traction force from the front stiffener (5) and/or back stiffener (6) towards the bearing zone (200) in the longitudianl direction of the ski.

Description

DEVICE FOR REDUCING THE PRESSURE OF THE SKI EXTREMITIES ON SNOW FOLLOWING SKI SUPPORT ON SKIING

The invention relates to an improved ski provided with a device intended to modify the distribution of pressure on the sliding surface of a ski as a function of the intensity of the force transmitted directly by the boot on the ski. The invention mainly applies to alpine skiing and monoskiing.

The main stress to which the ski is subjected is constituted by the weight of the skier, and by the reaction transmitted by the sliding surface on the ski. In particular, the skate or middle zone is the region that undergoes the most effort. The front and rear support areas at the contact lines are also subject to significant stresses due to the camber line. Depending on whether the ski is flat or in a turn, these three zones will undergo more or less significant efforts but for traditional skiing, the amplitude of the variations in the front and rear zones remain small. In other words, the effort made by the skier under certain conditions has only a slight influence on the pressure of the front and rear parts of the ski on the snow. The pressure distribution on the ski can be modified by the weight transfer operated by the skier forwards or backwards.

It is known that the behavior of the ski on snow can be modified, in particular its ease of initiation when cornering, its quality of driving when cornering or in a straight line, by influencing the camber of the ski, or even by playing on the longitudinal distribution of the ski pressure on the snow. By playing on this pressure distribution, it is known that one can make the ski more or less pivoting or more or less guiding, that is to say that one can promote its ability to turn easily, or to have great driving stability. For skis which are currently on the market, the pressure distribution of the ski on the snow is mainly determined by the internal structure of the ski, and by the method of assembly of the binding elements to the ski, that is to say with or without connecting blade between the front and rear elements. The pressure distribution can also be influenced by the intensity of thrust given to the recoil springs which determines the toe-in of the shoe between the fastening elements.

There are devices with attachments which allow the pressure distribution of the ski to be changed on the snow. Thus, European patent application No. 183586 describes a blade of elastic material of the spring blade type attached above the ski, between the binding elements and the ski. This blade has, at its front and rear ends, sliders through which vertically passes part of the forces to which the ski is subjected. This device however has the disadvantage of having modest performance for a large size. It is suitable for the case where both feet of the skier are in support for the same ski, to prevent the entire weight of the skier from being concentrated in the skate area. On the other hand, it is ill-suited in the case of a pair of traditional skis.

Other patent applications also relate to devices of the stiffener type attached to the upper surface of a ski base; which influences the stiffness characteristics of the ski. Mention may be made, for example, of French applications No. 2,670,392; No. 2,670,393: No. 2,675,390; No. 2,675,391; No. 2,689,411.

For these devices, it should be noted that the influence which they exert on the flexion of the ski is of the static type, that is to say that the position and / or the effort of the skier on his skis during the glide.

However, the applicant has found that such devices lead to a very guiding machine therefore very stable but conversely difficult to maneuver. On the basis of this observation, the applicant decided to seek solutions which could lead to the best compromise of stability / ease of pivoting in order to obtain a high-performance ski in all driving situations at high speed. In particular, it has been found that when flat or when engaging large curves at high speed, it is necessary to have a ski that follows the trajectory perfectly with great precision and good stability. It is therefore necessary to keep the qualities of the prior stiffening devices when skiing.

On the other hand, it was also noted that it was necessary to be able to influence the ends of the ski in a dynamic way, that is to say by the direct intervention of the skier, this in order to facilitate the pivoting of the ski in the event of need for a sudden change of course.

From the prior art, it is known that to facilitate pivoting around the center of gravity of the skier, it is preferable to relieve the ends of the ski from the pressure exerted by the weight of the skier. Such teaching is described in documents of the prior art such as in documents DE-GM-79 12 699 and FR 810762. The invention described in these two documents relates to a ski provided with an inverted cam base on which a normal camber stiffener is reported. Thus, when the ski is relieved of the weight of the skier, the ends are raised by the effect of the camber of the base and when the skier presses on the ski, the stiffener cancels the camber of the base and presses the ends on the snow. The disadvantage of these devices lies in the fact that at the time of cornering, no relief of the ends of the ski can occur due to the fact that the skier prints a great effort on the ski to avoid any skidding. It should be noted that such devices are ineffective and do not respond in terms of solution to the realities of operation of a ski on snow.

Finally, in the close prior art, document FR-A-2 686 798 is known which relates to a device which, on the contrary, aims to increase the pressure on the "active" ends of the ski by pressing the boot on the device. By "active" end, it is meant the parts in contact with the snow as opposed to the raised ends that are the tip and the heel. It is the opposite effect which is sought in the present invention.

The object of the present invention is therefore to propose a device which makes it possible to modify, dynamically, the pressure distribution of a ski on its sliding surface, that is to say which takes account during the sliding in the curve, the weight transfer of the skier due to his position on his skis, and the vertical thrust force of the skier so as to optimize the stability / maneuverability compromise of the ski.

For this, the invention relates to a ski in particular intended for the practice of alpine skiing which comprises a lower base having its own thickness distribution comprising a central part slightly arched between two contact lines, respectively, front and rear; said base being raised on either side of the contact lines; said central part comprising at least one front and / or, respectively, rear stiffening element, linked by one of the ends at the front of the central part, respectively, at the rear of the central part, l the other end being located in the support zone of the ski boot and being connected to at least one intermediate connecting means.

The ski is characterized by the fact that said intermediate means is located in said support zone of the boot and is in direct or indirect contact therewith so as to receive a vertical thrust (P) downwards; said means being capable of transmitting, in part at least said thrust, in the form of at least one tensile force from the front and / or, respectively, rear stiffener to the support zone in the longitudinal direction of the ski.

In other words, the overpressure force exerted by the skier on the occasion of a change of trajectory for example results dynamically in a relief of the pressure on the snow from the "active" ends of the ski. The latter becomes more pivoting. After the change of trajectory, the overpressure is removed so the stiffening elements then naturally play their role and the ski becomes precise and stable again.

According to another characteristic of the invention, the ski comprises a feeler member in direct connection with the sole of the boot on the one hand, and with said intermediate connecting means, on the other hand. The feeler member promotes the transmission of vertical stresses from at least part of the shoe sole.

According to an advantageous characteristic, the ski of the invention comprises a front stiffening element and a rear stiffening element linked together in the support region by means of said intermediate connecting means, said means being capable of transmitting said vertical thrust in the form of at least one tensile force directed along the longitudinal axis of the ski in the direction of bringing together or covering the ends linked together of the stiffening elements. Thus, it is advantageous to have a device which operates symmetrically or substantially symmetrically on either side of the skier's support zone for a more balanced behavior.

According to a particular characteristic, the intermediate means consists of at least one "L" shaped rocker which has a substantially horizontal branch on which the thrust of the shoe is exerted and a substantially vertical branch, each end of which is crossed by a hinge axis; at least one of the axes ensuring the articulation connection between the rocker (s) and the end of one of the stiffening elements; the other axis ensuring the articulation connection between the rocker (s) and the end of the other stiffening element and / or between the rocker (s) and the lower base. Such an intermediate element has the merit of being of a particularly simple construction and of reliable operation in difficult conditions of cold and frost. In addition, the transmission of forces is particularly efficient and direct.

According to another characteristic, the feeler member is linked directly or indirectly to the base by an articulation along a transverse axis and acts on said intermediate means in a substantially vertical direction by tilting around said articulation axis.

According to a particular characteristic, an elastic means of prestressing the feeler member is housed between the feeler member and the base, and whose characteristics (stiffness, stroke) are chosen so that the thrust (P) of the shoe on the intermediate connecting means is only exerted from a certain value (Pmin). Thus, provision is made for direct intervention by the skier on the distribution at the ends only from a certain effort threshold to be defined according to the conditions (weight and force of the skier, ski level, discipline, nature of the track, etc. ).

According to a particularly advantageous characteristic, an elastic means for prestressing the stiffening elements is located between the front stiffening element and the rear stiffening element so as to exert a compressive force on each element in the direction of their respective ends. In this way, it is expected that the device aims more particularly to cancel or even reverse the pressure exerted by the stiffening elements thus preloaded. From a very directional ski by the effect of the stiffeners, a ski is obtained with normal pressure characteristics at the ends or even reduced by the additional effort of the skier. Other objects, characteristics and advantages of the invention will emerge from the following description of particular embodiments, made in relation to the attached figures, among which:

FIG. 1 is a general side view of a ski according to the invention and equipped with front and rear fixing elements,

FIG. 2 is a top view of the ski of FIG. 1,

FIG. 3 is a side view in partial section of a part of the ski shown in FIG. 1,

FIG. 4 is an exploded perspective view at the level of the feeler member and of the connection of the stiffeners before mounting,

FIG. 5 is a simplified representation of part of the device in the rest position,

FIG. 6 is a simplified representation in the working position,

FIG. 7 is a view similar to that of FIG. 3 but according to a variant of the invention,

FIG. 8 is a side view in partial section of part of the ski according to a variant of the invention,

FIG. 9 is a simplified view of part of the mechanism of the invention showing, in particular, the connection of the front and rear stiffener between them according to a variant,

FIG. 10 is a simplified view showing a particular embodiment of the transmission between the feeler member and the intermediate connecting means,

FIG. 11 is a view similar to FIG. 9 but according to a variant,

FIG. 12 is a simplified top view of part of the mechanism of the invention according to a variant,

FIG. 12a is a simplified representation of the simplified mechanism of FIG. 12 along the line l-l, in a rest position,

- Figure 12b is a view similar to the view of Figure 12a in a working position.

In Figure 1, there is shown an alpine type ski which comprises a main part or base (1) having its own distribution of thickness and therefore stiffness. This base (1) can be divided into several separate parts including a central arched part (2) between two contact lines, respectively, front (20) and rear (21) when the ski is unloaded. The base also includes a raised front part constituting the tip (3) and a rear part constituting the heel (4); these two parts being arranged on either side of said central part (2).

The central part is surmounted by a stiffening element or stiffener (5) at the front and a stiffener (6) at the rear also; the front end (50) of the front stiffener (1) being linked to the base; as well as the rear end (60) of the rear stiffener. The connection method can be of the screwing, gluing, molding or any other suitable means. Outside this connection, each stiffener has a certain free length relative to the base. The stiffening blade is made of any suitable material capable of transmitting longitudinal stress.

Preferably, the material of the blade is chosen so that the blade also has elasticity in bending in a vertical plane. For example, it is made of plastic material possibly loaded with fibers. The two stiffeners (5, 6) freely crossing the area of each fastener through stirrups (31, 32) on which are fixed fastening elements. The stiffeners (5, 6) are interconnected in the support zone (200) of the shoe by an intermediate connecting means (7) as illustrated in FIG. 3. The intermediate means (7) is a means of articulation on which the ski boot (9) acts via a feeler member (8). The application of a thrust from the heel (91) of the shoe (9) on the feeler member (8) actuates the articulation or intermediate connection means (7) which acts in traction on the ends (51, 61 ) stiffeners (5, 6) in the direction of approximation or partial recovery thereof. Each stiffener being linked to the base (1) by their other end (50, 60); there follows a reduction in the pressure exerted on the snow in the front and rear areas of the ski, in the vicinity of the contact lines (20, 21). The ski thus becomes more pivoting.

The feeler member (8) is mounted on the rear stirrup (32) integral with the base and has two lateral sides on which the feeler member is articulated around a transverse axis (81). At a certain distance from this axis is the receiving surface (800) of the feeler member to receive all or part of the heel of the shoe (9). The feeler member can act on said intermediate means (7) in a substantially vertical direction by tilting around the hinge axis (81).

The stiffeners (5, 6) can be prestressed in compression by an elastic prestressing means (73) housed in a space separating the rear end (51) of the front stiffener (5) from the front end (61) of the rear stiffener (6). The compression force is exerted on each stiffener (5, 6) in the direction of their respective ends (51, 61). In this configuration, the application of an effort on the part of the skier will have the effect of reducing this prestressing, possibly until it is canceled. Beyond that, an additional effort may create a tensile stress on the stiffeners (5, 6) and a pressure relief at the ends of the ski.

The various parts constituting the invention according to a particular mode are visible in Figure 4 by way of example. Intermediate connecting means (7) comprises two lateral rockers (70, 71) which have, viewed from the side, approximately an "L" shape each with a horizontal branch (70a) and a vertical branch (70b). The two rockers are suspended around a first articulation axis (82) located at the upper end of the vertical branches (70b). This axis passes through a horizontal oblong hole (52) from the end of the front stiffener (5). Thus, when the ski is flexed due to a terrain accident, the stiffeners can be brought together over a certain length equivalent to the length of the oblong hole, without the rockers being actuated. In other words, the flexion of the ski is made independent, at least in part, of the operation of the feeler member by the shoe.

Each rocker is suspended around a second articulation axis (83) crossing the lower end of each vertical branch (70b). The axis (83) provides the connection between the rockers (70, 71) and the front end (61) of the rear stiffener (6). Also, the axis (83) is itself carried, at its ends, by the sides (320, 321) of the stirrup (32), at the level of oblong holes (320a, 321a) which are oriented according to a horizontal and longitudinal direction. It will be noted that the ends (51, 61) of the stiffeners are offset with respect to each other in two different horizontal planes parallel to each other, so as to allow the rockers to operate.

Each rocker comprises, at the level of the horizontal branch (70a), a bearing zone on which the feeler member (8) comes to rest in a vertical direction by means of two lateral beams (801) on the one hand and other from the receiving surface (800).

Preferably, the movement of the feeler member (8) is limited downwards and upwards. The limiting means are shown in the figures by a horizontal and transverse pin (84), located in the front part of the feeler member. The ends of the pin (84) circulate in vertically oriented slots or oblong holes (33) produced in the sides (320, 321) of the stirrup (32). The movement of the feeler member is limited by the abutment of the ends of the pin (84) in the upper or lower part of the slots (33). Of course, the pin (84) can be replaced by two projecting rod ends integral with the side members (801) of the member (8).

The simplified figures 5 and 6 show the operating mode of the device according to the invention. At rest, according to FIG. 5, the stiffeners (5, 6) are prestressed in compression in the longitudinal direction by the spring (73). When a sufficient thrust (P) is exerted on the receiving surface of the feeler member (8), the rocker (7) exerts a traction (T1, T2) on the stiffeners, which compresses the spring (73) ( figure 6). FIG. 7 illustrates a variant according to the invention in which a single front stiffener (5) is provided, the rear stiffener (6) having been omitted. In this case, the rocker (s) (7) is (are) connected (s) on the one hand to the rear end of the stiffener (5) by the axis (82) passing through the upper end of the vertical branch (70b) and on the other hand to the stirrup (32) by the axis (83) crossing the lower end of said vertical branch (70b). Of course, one can also provide the opposite case where it is the rear stiffener (6) which is present and the front stiffener (5) is omitted. In this case, the technical effect will only be felt in the rear part of the ski.

As shown in Figure 7, it can also be provided that an elastic prestressing means (802) is housed between the feeler member (8) and the base (1). Thus, according to the chosen characteristics of the elastic means (stiffness, stroke), the minimum thrust (Pmin) of the shoe can be adjusted from which the intermediate connecting means (7) is stressed. The elastic means can be an elastic pad made of elastomeric material or else a helical spring or the like. Of course, the use of this elastic means can be generalized to any embodiment, in particular to those previously described.

FIG. 8 illustrates another variant where the intermediate means or rocker (7) is biased in the front part of the support zone (200), at the level of the tip (90) of the shoe (9). The feeler member (8) is mounted on the front stirrup (31) integral with the base, around the transverse axis (81). The receiving surface (800) of the member (8) is in contact with the sole in the anterior region of the boot and therefore mainly picks up the stresses during the forward pressing of the skier. These stresses are generally of lower intensity than those in the rear region.

According to the particular mode of FIG. 9 showing only part of the means of the invention (without the feeler member, in particular), the stiffeners (5, 6) have linked ends (51, 61) consisting of removable and adjustable parts longitudinally relative to the rest of the stiffeners (5, 6). Each part is connected to the stiffener by suitable removable fixing means (52, 62) such as screws or any other means.

According to the mode of Figure 10 and 11, there is provided a means of adjusting the contact between the feeler member (8) and the intermediate connecting means or rockers (7). In the case of FIG. 10, it is a means of the screw / lock nut type (85) displaceable in a longitudinal slot (86). Thus one can adjust both the depth and the longitudinal displacement of the screw in contact with the rocker (7). In the case of FIG. 11, this involves providing in the feeler member different fixed tapped longitudinal housings (87, 88) having a shoulder of different depth and intended to receive an adjustment screw (89). The rocker used in the previous modes can of course be replaced by other equivalent intermediate connecting means fulfilling the same function. We can for example cite a rack type means, movement transmission means of the hydraulic or pneumatic type also.

As an advantageous example, FIG. 12 schematically illustrates a particular embodiment of the invention using an intermediate means (7) consisting of one or more element (s) made of deformable and elastic plastic or elastomer. Each element is included in a housing whose front and rear edges are constituted respectively by the front end (61) of the rear stiffener (6) and by the rear end (51) of the front stiffener (5). The lateral edges consist of lateral flanks (11) integral with the base (1), the width (L) of which is greater than the width (I) of the element in the rest state. Figures 12a and 12b show the operating principle of the intermediate means. The property of almost total incompressibility of the material of each element is used to transmit the vertical pushing force into the pulling force (T1, T2), of the stiffeners (5, 6). As in the previous modes, a feeler member (8) is used which deforms each element (7) in their housing, which causes the ends (51, 61) of the stiffeners to move apart and due to their particular arrangement illustrated in Figure 12, the stiffeners (5, 6) are stressed in tension.

Of course, one can also provide a particular mode with a single front (6) or rear (7) stiffener on which acts one or more deformable and elastic element (s) so as to create only one front or rear effect only.

The present invention is not limited to the embodiments which have been explicitly described, it also includes the various variants using equivalent means, the combinations of the various modes presented as well as the improvements available to those skilled in the art.

Claims

1) Ski particularly intended for alpine skiing, comprising a lower base (1) having its own thickness distribution and comprising a central part (2) slightly arched between two contact lines, respectively, front (20) and rear (21); said base being raised on either side of the contact lines; said central part comprising at least one front stiffener (5), and/or respectively, rear (6), linked by one of the ends (50, 60) to the front of the central part (2), respectively, at the rear of the central part (2), the other end (51, 61) being located in the support zone (200) of the ski boot (9) and being connected to at least one means connecting intermediate (7); said intermediate means (7) being located in said support zone and being directly or indirectly in contact with the shoe so as to receive a vertical thrust (P) from said shoe downwards; characterized in that said intermediate means (7) transmits, at least in part, said thrust, in the form of at least one traction force from the front stiffener (5) and/or, respectively, rear (6), towards the zone support (200) following the longitudinal direction of the ski.

2) Ski according to claim 1, characterized in that it comprises a feeler member (8) in direct connection with the sole of the shoe (9) on the one hand, and with said intermediate connecting means (7), d 'somewhere else.

3) Ski according to claim 1 or 2, characterized in that it comprises a front stiffener (5) and a rear stiffener (6); connected together in the support region (200) via said intermediate connecting means (7); said means being capable of transmitting said vertical thrust in the form of at least one traction force directed along the longitudinal axis of the ski in the direction of a rapprochement or an overlapping of the linked ends (51, 61) between them of the stiffeners (5, 6).

4) Ski according to any one of the preceding claims, characterized in that the intermediate means (7) consists of at least one rocker (70, 71) in the shape of an "L" which has a substantially horizontal branch (70a ) on which the thrust of the shoe is exerted and a substantially vertical branch (70b) each end of which is crossed by a hinge pin (82, 83); at least one of the axes (82, 83) ensuring the connection by articulation between the rocker(s) (70, 71) and the end of one of the stiffeners (5, 6); the other axis ensuring the connection by articulation between the rocker(s) and the end of the other stiffener and/or between the rocker(s) (70, 71) and the lower base ( 1).

5) Ski according to claim 2, characterized in that the feeler member (8) is linked directly or indirectly to the base (1) by an articulation along an axis transverse (81) and acts on said intermediate means (7) in a substantially vertical direction by tilting around said articulation axis (81).

6) Ski according to claim 5, characterized in that an elastic prestressing means (84) of the feeler member is housed between the feeler member (8) and the base (1), and whose characteristics (stiffness , race) are chosen so that the thrust (P) of the shoe on the intermediate connecting means (7) is only exerted from a certain value (Pmin).

7) Ski according to claim 3, characterized in that an elastic means of prestressing (73) of the stiffeners is located between the front stiffener (5) and the rear stiffener (6) so as to exert a compressive force on each element (5, 6) towards their respective ends (50, 60).

8) Ski according to claim 4, characterized in that the hinge pin (82) of the upper end of the vertical branch (70b) of the rocker(s) is(are) retained in a horizontal oblong hole (52) in the end of said front stiffener

(5).

9) Ski according to claim 8, characterized in that each end of the other articulation axis (83) of the rocker(s) cooperates at the level of horizontal oblong orifices (320a, 320b) made in a stirrup (32) comprising two lateral sides (320, 321) secured to the base (1).

10) Ski according to claim 9, characterized in that the feeler member is provided laterally with projecting rod ends cooperating with vertical oblong orifices (33) made in the lateral sides (320, 321) of said stirrup (32) so as to limit the travel of the feeler member (8) upwards and downwards.

1 1) Ski according to any one of claims 2 to 10, characterized in that the feeler member (8) comprises a substantially flat upper receiving surface (800), arranged in the region where the heel (91) of the shoe (9).

12) Ski according to any one of claims 2 to 11, characterized in that the feeler member (8) comprises a substantially flat upper receiving surface (800), arranged in the region where the tip is intended to be applied (90) of the shoe (9).

13) Ski according to any one of claims 3 to 12, characterized in that the ends linked together (51, 61) of each stiffener (5, 6) are made up of removable parts adjustable longitudinally relative to the rest of each stiffener (5, 6).

14) Ski according to claim 1, 2 or 3, characterized in that the intermediate means (7) comprises a means of the rack type, of the hydraulic or pneumatic type or of one or more element(s) made of plastic or elastomer deformable and elastic.