EP0045698B1 - Ski brake - Google Patents

Abstract

A ski brake comprising two pivotal arms having intermediate elbowed portions pivotally mounted in fixed bearings about an axis transverse to the ski, an operating pedal and a spring for restoring the pivotal arms to their braking position. A flexible and resilient metallic strip provides a connection between the control ends of the braking arms, is secured to an operating pedal actuated by the ski boot and is subjected to the action of a restoring spring and traction member. The ends of the resilient strip are fixed in cylindrical sleeves which are rotatably mounted on the control ends. When a boot is in position within the safety ski binding and the ski brake is therefore in a standby position of withdrawal above the ski, the resilient strip has a flat configuration and is located in practically the same plane as the traction member, thus preventing the appearance of a parasitic stress which would otherwise be liable to interfere with the operation of the ski binding.

Description

The present invention relates to a ski brake of the kind comprising two pivoting arms, both articulated around a horizontal axis transverse to the ski.

In certain known brakes, the arms also have the possibility of movement in the plane of the ski. An elastic return member constantly biases the arms in the active position in which the braking ends protrude below the plane of the sole of the ski and have a maximum mutual spacing. When the boot enters the safety binding, the braking ends are raised above the plane of the ski and then tilt parallel to it to get closer to each other. The braking ends are then in the retracted position above the ski and do not project laterally on the sides of the ski. This is an advantage for the skier, the braking ends not being exposed to the risk of catching on possible obstacles, such as roots, which may be on the track.

When the boot leaves the binding, the elastic return member causes the brake to be redeployed, the braking ends of which start by moving away from one another to cross the edges of the ski, then pivot down to crash. in the snow.

Many devices have been proposed, described for example in FR-A-2 409 061, FR-A-2 400 374 and FR-A-2 357 274 for controlling the retraction of the brake; these are generally relatively complicated, fragile and expensive.

However, a relatively simple ski brake of the type described is known, in which a naturally curved elastic blade, forming a pedal, connects the control ends of the arms opposite their braking ends to one another.

When the brake is in the active braking position, the curved elastic blade tends to bring the control ends closer to one another and therefore to separate the braking ends from each other.

When the shoe is in place, it crushes this blade, causing its extension and consequently the separation of the control ends and therefore the mutual bringing together of the braking ends.

When the boot escapes from the binding, the blade resumes its curved shape, which brings the control ends closer together and therefore the spacing of the braking ends which pass on each side of the ski then pivot downwards under the action of a return spring.

This brake is described for example in French patent n ° 76.11752 (Publication n ° 2 308 389).

This embodiment has the drawback consisting in the fact that, the leaf of the spring being crushed by the shoe, exerts under the sole thereof a high pressure which constitutes a parasitic stress which can disturb the normal operation of the safety binding. The use of a relatively strong blade being necessary to obtain effective braking, this parasitic constraint can reach an excessive and dangerous level.

The invention aims to remedy this drawback by providing a ski brake in which no parasitic stress is likely to interfere with the normal operation of the binding when the boot is in place on the ski and the brake in the retracted position at above it.

• - en position active de freinage la ligne d'action de l'organe de traction forme par rapport à la face de la lame un angle tel qu'il provoque sa flexion, ce qui a pour effet d'incliner les extrémités de commande des bras en les rapprochant et, par conséquent, d'écarter l'une de l'autre les extrémités de freinage,
• - en position escamotée, la ligne d'action de l'organe de traction soit à peu près parallèle à la face de la lame qui prend une configuration plane, ce qui a pour effet de redresser les extrémités de commande des bras en les écartant et, par conséquent, de rapprocher l'une de l'autre les extrémités de freinage.

According to the invention, the flexible elastic blade is integral with an operating pedal capable of being driven by the ski boot and pivotally mounted on the control ends of the arms around a horizontal axis transverse to the ski while the elastic return member is a traction member, one end part of which is fixed to the ski and the other end part acts in the central region of the blade, so that:

• in the active braking position, the line of action of the traction member forms an angle with respect to the face of the blade such that it causes it to flex, which has the effect of tilting the control ends of the arms by bringing them closer together and, consequently, moving the braking ends apart,
• in the retracted position, the line of action of the traction member is approximately parallel to the face of the blade which assumes a flat configuration, which has the effect of straightening the control ends of the arms by spreading them apart and , therefore, to bring the braking ends closer to each other.

When the boot is in place in the binding, the operating pedal being flat against the ski, it is possible by construction to provide that the transverse pivot axis of the arms, the line of action of the traction member and the blade (which has regained its natural flatness) are coplanar. Under these conditions, the action of the traction member is zero on the one hand to rotate the blade on itself and raise the operating pedal, on the other hand to rotate the arms around the transverse axis . The brake is then in equilibrium and the parasitic effort developed under the shoe is zero.

In practice, this arrangement must of course be avoided so that the brake can be recalled when the shoe escapes. However, a slight angular offset of the traction member makes it possible to obtain a restoring force which is sufficient to actuate the brake but insufficient to hinder the operation of the safety binding.

• - La figure 1 est une vue en perspective d'un premier mode de réalisation du frein à ski selon l'invention, en position active de freinage;
• - La figure la est une vue en coupe longitudinale de l'organe de traction servant au rappel du frein;
• - La figure 2 est une vue analogue à la figure 1, montrant le frein dans une position intermédiaire dans laquelle les bras du frein se trouvent dans un plan parallèle au plan du ski, mais leurs extrémités de freinage ne se sont pas encore rapprochées l'une de l'autre;
• - La figure 3 est une vue analogue aux figures 1 et 2 montrant le frein en position escamotée, les extrémités de freinage des bras étant rapprochées l'une de l'autre au-dessus du ski;
• - La figure 4 est une vue de dessus en plan, avec coupe partielle, montrant un second mode de réalisation du frein selon l'invention, dans une position intermédiaire, les extrémités de freinage étant relevées, mais non escamotées;
• - La figure 5 est une vue analogue à la figure 4, montrant le frein en position escamotée au-dessus du ski;
• - La figure 6 est une coupe transversale suivant VI-VI de la figure 5;
• - La figure 7 est une vue de dessus en plan avec coupe partielle d'un troisième mode de réalisation du frein selon l'invention, dans une position intermédiaire, les extrémités de freinage étant relevées, mais non escamotées;
• - La figure 8 est une vue analogue à la figure 7 montrant le frein en position escamotée au-dessus du ski;
• - La figure 9 est une vue en coupe transversale suivant IX-IX de la figure 8.

Other features and advantages of the invention will become apparent from the description which will follow, made with reference to the accompanying drawings which represent several non-limiting embodiments of the invention.

• - Figure 1 is a perspective view of a first embodiment of the ski brake according to the invention, in the active braking position;
• - Figure la is a longitudinal sectional view of the traction member for the return of the brake;
• - Figure 2 is a view similar to Figure 1 showing the brake in an intermediate position in which the brake arms are in a plane parallel to the plane of the ski, but their braking ends have not yet approached the one of the other;
• - Figure 3 is a view similar to Figures 1 and 2 showing the brake in the retracted position, the braking ends of the arms being brought close to each other above the ski;
• - Figure 4 is a top plan view, partially in section, showing a second embodiment of the brake according to the invention, in an intermediate position, the braking ends being raised, but not retracted;
• - Figure 5 is a view similar to Figure 4 showing the brake in the retracted position above the ski;
• - Figure 6 is a cross section along VI-VI of Figure 5;
• - Figure 7 is a top plan view with partial section of a third embodiment of the brake according to the invention, in an intermediate position, the braking ends being raised, but not retracted;
• - Figure 8 is a view similar to Figure 7 showing the brake in the retracted position above the ski;
• - Figure 9 is a cross-sectional view along line IX-IX of Figure 8.

Referring to Figures 1 to 3, there is shown a first embodiment of the ski brake according to the invention, which comprises two braking arms 1 each constituted by a suitably shaped metal wire. Each arm 1 has a bent part 2 articulated in a bearing 3 around a horizontal axis xx and transverse to the ski S. The bearings 3 are carried by a plate 4 fixed to the ski S by suitable means not shown such as screws. The shape of the bearings 3 allows a certain angular movement of the bent parts 2 relative to the transverse axis xx. Each of the arms 1 consists, in a well known manner, of a control end 6 and of a braking end 7 provided with an overmolded pad 8. Each control end 6 has a transverse end portion on which is rotatably mounted a cylindrical ring 15. A flexible blade 14, made of a suitable material such as a spring steel, arranged transversely with respect to the ski, connects one to the other, the two rings 15, the ends of the blade 14 being embedded in these. The blade 14 passes through an operating pedal 5 with which it is secured in its central region. An elastic return member, in the form of a traction member, is articulated by one of its ends to lugs 12 carried by the plate 4 and by its other end to the operating pedal 5. In the example shown l 'traction member comprises a cylindrical tube 11, a tie rod 13 provided with a head 13a which can slide in the tube 11, and a compression spring 9 disposed between the head 13a and the bottom of the tube.

This embodiment has the advantage of being particularly robust and waterproof; however, it would be possible to provide a traction member of a different type, for example, a simple traction spring.

• Le ressort 9 exerce constamment sur la lame 14, par l'intermédiaire de la tige de traction 13 et de la pédale 5, une force dont la direction forme un certain angle avec la face principale de la lame 14 (et avec la pédale 5 portée par celle-ci). De ce fait, la lame 14 fléchit élastiquement et les bagues 15 se rapprochent l'une de l'autre tandis que leurs axes forment un V (très ouvert) car ils prennent une position légèrement inclinée par rapport à l'axe transversal xx. Les bras 1 basculent corrélativement par leurs parties intermédiaires coudées 2 dans les paliers 3, de sorte que les extrémités de freinage 7 avec leurs patins 8 sont écartées au maximums vers l'extérieur du ski S (voirfigure 1).

The operation of the ski brake which has just been described is as follows:

• The spring 9 constantly exerts on the blade 14, by means of the traction rod 13 and the pedal 5, a force whose direction forms a certain angle with the main face of the blade 14 (and with the pedal 5 carried by it). Therefore, the blade 14 flexes elastically and the rings 15 approach each other while their axes form a V (very open) because they take a slightly inclined position relative to the transverse axis xx. The arms 1 tilt correlatively by their bent intermediate parts 2 in the bearings 3, so that the braking ends 7 with their pads 8 are spread as far as possible towards the outside of the ski S (see FIG. 1).

During the fitting of the binding, the shoe presses on the pedal 5 and on the control ends 6 of the arms 1. These pivot around the axes xx to come occupy the intermediate position shown in FIG. 2, in which the pads braking 8 are in a plane above the ski but are further apart from each other at most, towards the outside of the ski. The shoe continuing its descent against the ski, the pedal 5 will now pivot by rotating the blade 14 on which it is integral. The face of the latter therefore switches from its initial position in which it makes an angle with the line of action of the spring 9, to take a position practically parallel to the plane of the ski S, illustrated in FIG. 3. As and measurement of this tilting, the blade 14 gradually presents at the line of action of the spring 9 no longer its face, but its edge; the spring 9 therefore acts on a blade 14 whose moment of inertia increases so that at the end of the stroke it can no longer ensure its flexion. During tilting, the blade which was curved therefore takes on a planar configuration, and therefore its ends separate the rings 15, the axes of which take a transverse direction, from one another. The sections 2 tilt in the bearings 3 and the braking ends 7 (and their shoes 8) approach each other to come to occupy a retracted position above the ski (see Figure 3). In this position, the line of action of the spring 9, materialized by the traction rod 13, is practically located in the plane of the flat blade 14 so that the force tending to bring the brake back to the active braking position is extremely low and therefore the parasitic stress exerted under the shoe is negligible and not disruptive.

When the shoe leaves the binding, the spring 9 recalls, by means of the traction rod 13, the pedal 5 and the blade 14 which gradually tilt, the rings 15 swiveling on the end portions of the control arms 6 ends 1 This movement is obtained by virtue of the fact that the tie rod 13 is hooked under the pedal 5, eccentrically with respect to the axis of the rings 15. The blade again having its main face to the axis of traction of the rod 13 , the blade 14 curves, and the pads 8 move away from one another by crossing the edges of the ski (FIG. 2). Then the traction member 13 causes the raising of the control ends 6 of the arms 1, the latter pivoting about the transverse axis xx while the pads 8 come to be placed in the braking position, projecting below the plane of the ski sole (Figure 1).

It will be noted that, for a given blade, the maximum deflection of the blade and, correspondingly, the best retraction of the arms are obtained when, in the intermediate position of FIG. 2, the traction member acts perpendicular to the blade. However, this arrangement, which has been adopted in the various embodiments shown for the simple purpose of simplification, is not perfect. Indeed, the vertical position of the operating pedal makes it difficult to place the shoe in the binding. Practice has shown that if the pull rod forms an angle of around 60 ° with the elastic blade, both good retraction and easy fitting of the binding are obtained.

In the second embodiment of the brake illustrated in FIGS. 4 to 6, the ends 14a of the blade 14 are engaged and guided in openings formed in the sides 16 of the operating pedal 17, the rotation of which by the shoe consequently entails the pivoting of the blade 14 on itself. On the other hand, the ends 14a pass through sleeves 18 similar to the sleeves 15 of the previous embodiment, and which rotate on the control ends 19 of the arms 21. The traction rod 13 is articulated on a transverse axis 20, integral with a stirrup 22 crossed by the central zone of the elastic blade 14.

The operation of this alternative embodiment is similar to that of the previous one, with the difference that the tilting of the blade 14 on itself is no longer caused by its central zone, but by its ends embedded in the lateral wings 16 of the pedal 17.

In the third embodiment shown in Figures 7 to 9, the blade 14 is embedded by its central region in a median extension 23 of the operating pedal 24. Furthermore, its ends are engaged in rings 18 journalling on the ends of control 19 of the arms 21, as in the embodiment of FIGS. 4 to 6. In addition, the traction rod 13 of the return spring 9 is articulated on a transverse axis 25 mounted in the extension 23.

In the active braking position, the blade 14 has the curved shape visible in FIG. 7, under the effect of the restoring force exerted by the spring 9 on the pedal 24 by the extension 23 thereof. At the same time, the intermediate bent parts of the pivoting arms 21 are in abutment inside the associated fixed bearings 3, the arms 21 being in the position illustrated in FIG. 7.

When the shoe enters the binding, it presses on the pedal 24 which then pivots, causing the blade 14 to rotate around itself, until it comes to be placed in a plane parallel to the surface of the ski, containing the axis of the traction rod 13.

In the various embodiments described, no parasitic force is exerted by the elastic blade connecting the control ends of the braking arms when they are in the retracted position above the ski, and this because the plane of this blade contains the axis of the restoring force of the brake in its active position, which constitutes an essential advantage of the invention compared to previous embodiments.

Claims (4)

1. Ski brake comprising two pivotal arms (1,21) both pivotally mounted about a horizontal axis (x-x) located transversely with respect to the ski with a possibility of angular displacement in the plane of the ski, a flexible resilient strip (14) disposed transversely and providing a connection between the control ends (6, 19) of the arms which are opposite to their braking ends (7), and an elastic restoring member for continuously urging the arms to the active position in which the braking ends project beneath the plane of the sole of the ski and are located in a position of maximum relative spacing, characterized in that the flexible resilient strip (14) is secured to an operating pedal (5, 17, 24) which is capable of displacement by means of the ski boot and is pivotally mounted on the control ends (6, 19) of the arms (1, 21) about a horizontal axis which is transverse to the ski whilst the elastic restoring member is a traction member, one end portion (11) of which is attached to the ski and the other end portion (13) of which produces action in the central region of the strip (14) in such a manner as to ensure that:

- in the active braking position, the line of action of the traction member (11, 13) is inclined with respect to the face of the strip (14) at an angle such that it causes flexural deformation of the strip, thus having the effect of inclining the control ends (6, 19) of the arms towards each other and therefore of outwardly displacing the braking ends (7) with respect to each other,

- in the position of withdrawal, the line of action of the traction member (11, 13) is approximately parallel to the face of the strip (14) which assumes a flat configuration, thus having the effect of restoring the control ends (6, 19) of the arms to their positions of relative outward displacement and therefore of inwardly displacing the braking ends (7) with respect to each other.

2. Ski brake in accordance with claim 1, characterized in that the central region of the strip (14) is inserted in the pedal (5, 24), an end portion of the traction member (11,13) being attached to this latter whilst the ends of the strip (14) are rigidly fixed to sleeves (15, 18) forming bearings in which the control ends (6, 19) of the arms (1, 21) are rotatably mounted.

3. Ski brake in accordance with claim 1, characterized in that an end portion of the traction member (11, 13) is directly attached to the central region of the strip (14) whilst the end portions (14a) of the strip (14) are engaged and guided within openings formed in lateral flanges (16) of the pedal (17).

4. Ski brake in accordance with any one of the preceding claims, characterized in that the traction member comprises a cylindrical tube (11) provided with an end wall, a tie-rod (13) which passes through the end wall of the tube (11) and has a head (13a) forming a piston slidably fitted within the tube (11), and a compression spring (9) interposed between the head (13a) and the end wall of the tube (11).

Images