Support plate for a ski binding

Abstract

A system for changing the stiffness of a ski includes an engagement member attachable to a ski and having a free end, and an impedance device engageable with the free end of the engagement member as the ski bends to change the stiffness of the ski.

Description

FIELD OF THE INVENTION

This invention relates to ski control apparatus for varying the characteristics of a ski according to the nature of the snow being skied upon, the type of skiing being performed, the nature of the ski and the skill of the skier, to improve the quality of the skiing and safety of the skier. It relates in particular to apparatus which vary the stiffness of the ski according to the foregoing conditions.

DESCRIPTION OF BACKGROUND AND RELEVANT INFORMATION

Important conditions affecting downhill skiers are the nature of the snow, the type of skiing to be done, the type of skis and bindings used and the skill of the skier. The snow and the ski run can vary during a day, while the ski and the skier are generally invariable. The snow can range from ice hard snow, to very loose or soft snow, sometimes called powder snow. There are profound differences in skiing turns and speed according to the type of snow being skied upon. One primary characteristic of a ski is its ability to bend or flex as it carries a skier. A ski flexes and counterflexes, and keeps the skier in control as he or she follows the contour of a slope and enables a skier to manipulate the skis as he or she bounds and rebounds down the slope. In racing events, the snow can be ice hard both to increase the skier's speed and to avoid ruts in the snow. Hard snow may limit the bending of the skis. Turning is mainly accomplished in hard snow by the skier tilting the skis to dig the edges at the bottom of the ski into the snow by shifting his or her weight and body position. On the other hand, the ski can bend a large amount in powder snow. The longitudinal sides of skis are convex arcs, and it is through the use of the side cuts and bending of the ski that the skier turns; the edges of the skis are of much less importance in turning in powder snow. Regular snow, that is snow whose texture and packing is between hard snow and powder snow, presents other problems to the skier. Experience, communications with racers and other skiing experts, and testing, indicate that a ski stiffer underfoot of the ski boot may be preferable in very hard snow conditions while an overall more flexible ski appears to be preferable in soft snow conditions. An intermediate situation is preferable for snow of intermediate softness. It is also known that a ski loosely attached to the skier transfers little energy from the ski to the skier when the ski encounters obstacles, thus resulting in higher speed. However, a loose attachment results in loss of ski control in turns; hence it is desirable to have a loosely connected ski when traveling essentially in a straight line for greater speed and a tightly connected ski when making turns for greater control.

The vibration characteristics of skis are also believed to be important. Skis have several vibration modes which are exhibited during skiing. High frequency vibrations break the contact between the ski bearing surface and the snow, which improves speed. On very hard snow conditions, the breaking of the contact between running surface and snow does not result in the same level of benefit but the ski still vibrates resulting in audible and perceptible chatter. A reduction in chatter is desirable in these conditions. Thus different requirements in underfoot stiffness and vibration exist depending on snow conditions. The ski designer, faced with the different kinds of snow, the different types of skiing, and variations in skiers and their bindings, can only develop skis which can handle all of these varying characteristics reasonably well but are not optimized for any specific condition.

All ski bindings have an effect on ski stiffness underfoot. When a ski bends during skiing, the distance between the toe piece and the heel piece varies since they move relative to each other with the upward curvature of the ski. However, the length of the ski boot sole remains constant. Therefore, there is generally a limited movement rearwardly of the heelpiece in a clamp on the ski to keep it in contact with the boot. The force required to move the heel unit back results in a stiffening of the ski section directly under the binding and boot. It is believed that most ski bindings on the market fall into this category. Therefore ski manufacturers take this stiffening action of the binding system into consideration in the design of the ski. The underfoot stiffness of the ski/binding combination is thus optimized for the type of skier and preferred snow conditions the ski was intended for. Different binding systems and separate devices to be used in conjunction with the ski and commercially available bindings have been manufactured to either increase or decrease the underfoot stiffness of the basic binding/ski configuration. Other devices can effect the normal vibration of a ski. Combinations which decrease stiffness underfoot may improve soft snow skiability while deteriorating skiability towards the end of the hard snow spectrum. Combinations which increase stiffness have the opposite effect.

In some systems, the binding is constructed to render the ski more flexible. In the ESS v.a.r. device, a boot support plate having a forward portion which is slidable in a channel on the ski, should render the ski more flexible. However, the support plate is fixed with additional fastening means to the ski, and thus is believed to limit its benefit on soft snow. The fixing of the support plate decreases the bending of the ski.

The Tyrolia Freeflex system utilizes a flexible plate attached to the top of the ski. The plate is fixed to the ski at the toe of the binding and is held in place about the heel by a slidable clamp fixed on the ski. Both toe and heel binding units are affixed on the boot support plate. When the ski bends, the heel clamp moves closer to the toe unit but the flexible plate is allowed to slide rearwardly reducing the tendency of the heel unit to move towards the toe unit as in a normal binding configuration. The ski is thus allowed to flex more underfoot. The plate is allowed to move in the slidable clamp but is also held to the ski by an additional sliding point between the toe and the heel. This mounting configuration increases sliding friction and thus the overall decrease of ski stiffening is relatively small. Devices of this nature are disclosed in U.S. Pat. No. 3,937,481.

Most ski binding manufacturers produce bindings which increase the stiffness of skis. The stiffness of a ski provides a firm edge to drive into the snow for making turns in hard or intermediate snow. In this respect, it is much like an ice skater who drives his or her blade into the ice to make a turn. A flexible blade would detract from the skater making a turn, just as a very soft ski in the section directly below the boot would detract from the skier turning in hard snow.

Some expert skiers performing giant slalom or super giant slalom have found that their turning ability is enhanced when they attach to the ski, such as by gluing, a thin plate on top of the ski in the binding area. This added plate increases the distance between the skier's boot and the edges of the ski, and enhances the leverage which the skier has to drive the edges of the ski into the snow. WIPO Document 83/00039 discloses a device wherein glue and an elastomeric material hold a plate for supporting a toe piece and heel piece to the ski. The elastomeric material absorbs some of the vibration of the ski on the hard snow and relieves some of the discomforting noise of the ski rapidly smacking against the snow. Furthermore, the device stiffens the ski/plate/binding combination in the underfoot area of the ski improving edge control on hard snow. In another device called the Rossi-Bar and disclosed in European Patent Office Publication No. 0409749, a support bar on the ski has stops of elastomeric material at its forward and rearward ends. However, the bar is locked to the ski by clamps along the length of the bar, and it is the clamps and not the rubber stops which prevent the bar from sliding on the ski. Thus, the plate reduces the bending of the ski. In U.S. Pat. No. 3,937,481 mentioned earlier, a ski binding having an elongated plate is slidably mounted thereon for cushioning the skier when a forward abutment is encountered. Only the forward or toe portion of the system is fixed to the ski, so that the plate allegedly follows the bending of the ski. The device in fact impedes the bending of the ski since it is strapped to the ski in a number of places. A similar device with similar shortcomings is disclosed in Austrian Patent 373,786. A device of this type is sold under the name Derbyflex. It has been believed by many experts that raising the ski binding with such a plate detracts from the skier's ability to control the ski, since it was thought that the skier had to be close to the snow to "feel" the snow and ski accordingly. The present inventors and other manufacturers believe that this notion is wrong for most types of skiers, and that holding a ski boot somewhat high over the ski increases his or her ability to control the ski. Other patents disclosing ski bindings for increasing stiffness in skis include German Patent 2,135,450 and European Publication 0409749A1.

Even though the added plate is beneficial, it only applies to skiing on hard snow where a stiffer underfoot ski is desirable. When used on softer or powder snow, the added stiffness detracts from the skier's ability to control the ski since easier bending adds to the turnability of the ski in soft snow.

Other devices are known having movable boot support plates on skis. For example, U.S. Pat. No. 4,974,867 discloses a shock absorbing buffer disposed between a ski and a binding, and is not really related to the stiffness of the binding.

The skill of the skier is another condition which the skiing apparatus should take into consideration. Although stiff skis are beneficial to good skiers in events such as giant slalom and super giant slalom, novice skiers should generally use flexible skis for all events, since they enable reasonable performance even though edge control in turns may be sacrificed.

The skis are generally desired to have a greater degree of flexibility when they are travelling down the fall line of a slope, and to be stiffer when they enter into and continue a turn. Skis heretofore have generally been incapable of changing their flex as they move into or out of a turn.

The inventors are unaware of any ski bindings or skis which are adaptable to vary the stiffness or change the vibration characteristics as skis enter a turn, continue a turn, or exit from a turn.

BRIEF DESCRIPTION OF THE INVENTION

It is an object of the invention to provide an improved device for controlling snow skis according to the nature of the snow, the skiing to be done, the type of skis, the skill of the skier and/or the turning direction of the skis.

Another object of the invention is to provide a support plate for a ski binding which controls the stiffness of skis in different skiing conditions.

Another object is to provide a device for controlling automatically the stiffness of skis in various turning conditions.

It is an object of the present invention to provide a device for controlling the stiffness of skis incorporating a support plate fixable to a ski and having a slidable portion, and an impedance device for controlling the slidable device to obtain the desired stiffness.

It is another object of the present invention to provide a continuously adjustable stiffness device for a ski.

It is still another object of the present invention to provide a ski binding for controlling the stiffness of the ski, wherein an impedance device changes position when an inertial force is acting thereupon.

It is another object of the present invention to provide a support plate assembly having a rotatable impedance device which stiffens the ski when an inertial force is acting on the impedance device, such as when the ski is running on its edge.

It is yet another object of the present invention to provide a ski binding for controlling the stiffness of the ski, wherein flexing of the ski is prevented when the ski is moved into a turn, thus allowing short, rapid turns to be accomplished with precision, even on hard snow.

It is still another object of the present invention to provide a ski binding for controlling the stiffness of the ski, wherein little or no stiffening of the ski occurs, when the ski is moving in a direction of the fall line of the slope, and an increase in the stiffening of the ski occurs, when the ski is moved into a turn.

It is a general object of the present invention to provide an improved ski control system for use with various types of snow, different degrees of skill of the skier and different skiing events, which system is efficient to manufacture and to use.

Other objects will become clear from the description to follow and from the appended claims.

One part of the present invention relates to controlling the stiffness of the ski to make the ski more suitable for different types of snow, different skiing events, different skills of the skier, and different types of ski. In fundamental form, this part of the invention includes an engagement member which is fixable at one location, to the ski, and an impedance means which effectively engages the engagement member to change movement of the non-fixed or free portion of the engagement member as bending moments are applied to the ski.

According to one embodiment of the present invention, a rotatable pivot arm is arranged on the ski adjacent to the free end of the support plate, whose opposite end is fixed to the ski. An inertial force acting on the pivot arm causes said pivot arm to rotate relative to the free end of the support plate. While the inertial force is acting, the pivot arm increases the stiffness of the ski as bending moments are applied to the ski.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood when reference is had to the following drawings in which like numbers refer to like parts, and in which:

FIG. 1 is a schematic drawing showing an engagement means as a support plate, and an impedance means as an adjustable stop.

FIGS. 2 and 3 show two settings of the apparatus shown in FIG. 1.

FIG. 4 is a schematic drawing of the apparatus of FIG. 1, but with an adjustable clamp.

FIG. 5 is a schematic drawing showing where the impedance means includes a progressively variable member as the ski flexes and counterflexes.

FIG. 6 is a schematic drawing of a stiffness system having a screw adjustable stop.

FIG. 7 is a schematic drawing of another form of the stiffness system for a ski where the adjustable stop is a transversely movable member.

FIG. 8 is a schematic drawing of still another form of the stiffness system where the adjustable stop includes an eccentric rotatable on a horizontal axis transverse to the ski.

FIG. 9 is a schematic drawing of a form of a stiffness system where the adjustable stop includes an eccentric rotatable about an axis vertical to the ski.

FIG. 10 is a schematic drawing of a form of a stiffness system where the impedance means is a continuously variable bias device including a friction member.

FIG. 11 is a schematic drawing of a form of a ski stiffness system where the impedance means is a continuously variable device.

FIG. 12 is a schematic drawing of a form of a ski stiffness system where the impedance means includes both a discrete stop device and a continuously variable device.

FIGS. 13 and 14 are schematic drawings of a ski stiffness system where a hydraulic system comprises the impedance means.

FIG. 15A is an exploded isometric view of the rear part of a support plate assembly mounted on a portion of a ski.

FIG. 15B is an exploded isometric view of the forward part of a support assembly shown in FIG. 15A, with the cover plate displaced from the assembly.

FIG. 16 is a plan view of the support assembly of FIG. 15 without a cover plate.

FIG. 17 is a cross-section of the support assembly along the line XVII--XVII of FIG. 16.

FIG. 18 is a cross-section of the support assembly along line XVIII--XVIII of FIG. 16.

FIG. 19 is a plan view of a different stiffening system, without a cover plate.

FIG. 20 is a cross-section of the previous device taken along the longitudinal centerline of FIG. 19;

FIG. 21 is a cross-section of an end of a support plate assembly of an embodiment of the invention supporting the front jaw of a safety ski binding;

FIG. 22 is a plan view of the end of the support plate assembly according to FIG. 21, but with the front jaw of the safety ski binding removed therefrom;

FIG. 23 is an isometric view of the support plate assembly of FIG. 22;

FIG. 24 is a plan view of a support plate assembly of the invention disposed in a reinforcing position different from that shown in FIG. 22;

FIG. 25 is a plan view of the support plate assembly of the invention disposed in yet another reinforcing position;

FIG. 26 is a schematic drawing of the support plate assembly embodiment of the invention shown in FIGS. 22-25.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

A stiffness controlling assembly 101 is shown in FIG. 1. The assembly includes an engagement means which can be a support plate 103, one of whose ends 105 is fixed to the ski 107 as indicated by fastening member 108 and its second end 109 is a free end which can slide in a longitudinal direction of ski 107 within guide means such as a support clamp 111. For the sake of this discussion, end 109 is closest to the forward end of the ski. An impedance means, shown here as an adjustable member, control member or stop 113, can be moved forwards or rearwards to preselected positions as indicated by the arrow 115 within its holding member or clamp 117. As shown, adjustable stop 113 can be moved relative to plate 103 and ski 107, within clamp 117 as indicated by arrow 115. Referring to FIG. 4, a movable clamp 121 can be moved as well with stop 113 held therein for preliminary adjustments, such as by a store or ski shop, to set the stiffness controlling assembly for the type of ski and skill of the skier, as indicated by arrow 119. A space of variable distance between stop 113 and end 109 is designated by the letter S.

When assembly 101 is to reduce the bending of the ski, as for example when the ski is to be turned in hard snow, adjustable stop 113 is moved to engage free end 109 of support plate 103, so that S equals 0, as shown in FIG. 2. This renders plate 103 substantially unable to move as bending moments are applied to the ski, and makes the ski stiff beneath plate 103. When the ski is to have its bending unimpaired, stop 113 is moved away from plate 103 as shown in FIG. 1, with S having a relatively high value. Then, regardless of the bending of the ski 107, plate 103 cannot engage stop 113, and no additional stiffness is added to the ski. For an intermediate stiffening condition, as where the skier is making turns on regular snow, S is set to a moderate value as shown in FIG. 3, so that free end 109 only contacts stop 113 during turns when the ski bends sufficiently for the contact to occur, to avoid further bending and improve edge control. The assembly could be arranged so that stop 113 is only set for intermediate stiffness control as shown in FIG. 3, in which holder 117 would not allow the adjustment of stop 113.

It should be noted at this time that the foregoing and many of the drawings to follow are schematic in nature, and that S need not be a complete space but could have some substance therein; however, the stiffening feature of the invention will nonetheless apply. Also, the support plate 103 has been shown as an integral member, but it could include a number of members whose effect is as shown for stiffening the ski. Likewise, the adjustable member or stop can have different forms, some of which are shown below.

Another form is illustrated schematically in FIG. 5, showing an embodiment where a substance is included in space S. As in the previous Figures, the assembly 151 of FIG. 5 includes a plate 103 held fast at one end to ski 107 by an attachment 108, and its free end 109 is supported for sliding movement in support clamp 111. An adjustable stop 113 is held by a clamp 117. A biasing means such as a coil spring 153 is connected between the end of free end 109 and the end of stop 113 facing it. As free end 109 moves towards stop 113 when ski 107 bends, spring 153 compresses. As spring 153 compresses more with increased bending, the spring forces get progressively greater, resisting the sliding of free end 109. This impedes further bending of the ski. As ski 107 continues to bend, the spring eventually becomes totally compressed, S declines to 0 (S being the distance between the end of free end 109 and the end of the totally compressed spring 153). At this point, assembly 151 is set for turning in hard snow, and plate 103 is unable to slide towards stop 113 and the ski beneath plate 103 is stiff. The counterflexing movement of ski 107 is easier as the ski continues to unbend, since the tension on spring 153 gets progressively less. When the ski is unloaded in this configuration, spring 153 releases its energy against stop 113 and free end 109 of plate 103, causing the ski to counterflex with progressively greater energy and speed. This, in turn, allows the skier to unweigh during counterflex, so that the skiing apparatus rather than the skier absorbs much of the shock as the skier goes down a slope.

A schematic of another embodiment 201 is shown in FIG. 6. Here, a support plate 203 is mounted above a ski 107, with one end, here its rearward end (not shown), fixed to the ski, and its opposite end which is free, clamped for sliding engagement over the ski by clamps or guides 205. Free end 207 is mounted for engagement with a control member or an adjustable stop 209 which is urged forwardly or backwardly by a screw 211 having threads 213 and a head 215. Screw 211 is mounted in a housing 217. A base plate 219 having thread receiving slots 221 is mounted beneath housing 207 on ski 107. With adjustable stop 209 in engagement with free end 207 of the support plate, the support plate 203 is in a stiff configuration, and cannot bend with the ski but rather restricts the ski from bending beneath assembly 201. In this implementation, the space S between free end 207 and adjustable stop 209 can be adjusted simply by turning screw 211. With S=0 the ski is relatively stiff underneath assembly 201. If S is very large, assembly 201 has essentially no impact on the stiffness of the ski under the assembly. The skier can also adjust S for different relatively small values to stiffen the ski more or less during turns.

FIG. 7 shows a transversely movable assembly 301 as part of another embodiment. Here, a partial top view of the ski 107 includes a support plate 303 which is fixed to the ski at one end, here the rear end, and which is free at its other end 305. End 305 has a narrow portion 307 which ends in a forwardly facing abutment 309. Transversely movable assembly 301 comprises a transversely movable control member 311, a housing 313 including a top wall 315, a base 317, walls 319, 321, and an aperture 327. Member 311 is mounted for movement transverse to ski 107, and has a rearwardly facing protuberance 323 with a rearward abutment face 325 and a peg or handle 329 attached to slide 311 which extends through aperture 327. Surfaces are provided defining a recess 331 which extends partly transverse to the ski and is adjacent protuberance 323. Member 311 can be moved across the ski by sliding peg 329 along aperture 327. Top wall 315 retains member 311 in place. Support wails 321 and 319 extending transverse to the ski are provided for maintaining member 311 in place when member 311 is in either of its positions, i.e., on the upper part of FIG. 7 when recess 331 faces abutment 309, or when (as shown) abutment 325 opposes abutment 309.

When the ski is to be placed in its extremely stiff mode, such as when the skier is going to perform giant slalom or superior giant slalom events in hard snow, the skier moves slide 311 so that the slide abutment face 325 engages abutment 309 as shown in FIG. 7. As the ski attempts to bend or flex, support plate 303 is held fast by member 311, giving the ski its stiff underfoot quality, giving the skier more control during his turns on the ski run. On the other hand, when the ski is to be used in softer snow, slide 311 is moved upward so that recess 331 faces abutment surface 309. In this setting plate 203 is free to move forward when the ski flexes and the ski is not stiffened. This embodiment, shown with two positions could be implemented with additional positions and intermediate recesses for obtaining intermediate stiffening conditions.

Still another embodiment is shown in FIG. 8. Here, a support plate 403 is fixed at one end, shown here as its rear end towards the back of ski 107, and has a front end 405. A clamp or guide 407 holds plate 403 for sliding engagement relative to ski 107. A retaining member 409 has a rearwardly extending control arm 411 having a downwardly extending foot 413 whose rearwardly facing face 415 is an abutment or contact 415. The retaining member 409 includes a horizontal cylinder 417 having its axis perpendicular to the axis of the ski. An axis of rotation 419 is offset from the natural rotational axis. Cylinder 417 is rotatable about an axis 419 forward of the center of rotation of the foregoing cylinder by means of a tool such as a screw driver inserted into the head 421 of the eccentric. Rotation of head 421 counterclockwise rotates eccentric 424 counterclockwise, moving the arm 411 forwardly and away from the supporting plate 403. Sufficient movement of arm 411 provides a space between abutment 415 and the free end 405 of support plate 403, providing a space between the two members so that support plate 403 allows limited bending of ski 107. The further forward arm 411 is from support plate 403, the more bending is possible.

Referring next to FIG. 9, the device somewhat similar to that shown in FIG. 8 is illustrated. Here, a support plate 503 includes one end which is fixed to the ski (not shown), which here is the rear end of the support plate, and a forward end 505 which is tapered towards its longitudinal axis to form a forwardly extending leg 507 from which two legs 509 extend on opposite sides of a centrally located recess 511. Forwardly of the support plate is disposed an eccentric adjustment or control member 513 having a cylindrical member 515 and with a turning head 517. Eccentric 513 rotates about the central axis of cylinder 515 as head 517 is rotated. Adjustment member or stop 513 includes a follower 519 defining a cylindrical bore in which cylindrical member 515 is concentrically located, and a rearwardly extending leg 521, terminating in a transverse leg 523 having a rearwardly extending abutment face 525. The latter abutment face faces abutment face 527 of support plate 503. The follower has flat surfaces 529 on opposite sides thereof for engagement with opposite, external surfaces 531 of spring 533 extending from a base plate.

The stiffness of the apparatus shown in FIG. 9 depends upon the location of adjustment face 525 and the abutment face 527 of support plate 503. In its rearward position, the adjustment member engages face 527 of support plate 503, so that the support plate cannot move relative to the ski, to render the ski stiff. If the eccentric is turned counterclockwise, the follower moves forwardly and creates a space with forward part 509 of the support plate 503. If the space is sufficient so that no amount of bending will cause surface 525 to engage the support plate 503, considerable bending of the ski is possible, and would be particularly useful in powder snow. On the other hand, where the ski is to become stiff only in conditions of hard curves, the eccentric is moved to create a space between abutment surfaces 525 and 527. When there is not sufficient bending of the ski, as in straight skiing down a slope, the support plate allows the ski to bend. However, if there are hard turns made, the rearwardly facing abutment surface 529 engages the forwardly facing abutment surface 527, rendering the ski stiff and inflexible. The rotation of the eccentric thus determines the spacing between the two abutment surfaces and the relative stiffness of the ski.

Referring next to FIG. 10, a stiffness controlling assembly 601 is shown including a support plate 603 which is fixed to the ski 107 at one end, here the rear end of the plate, and is free at its opposite end, which shown here is the forward end 605. The free end has tapered portions at the upper and lower part of plate 603 with inclined faces shown at 607 and 609, which run transverse to ski 107. An adjustment, control or retainer member 611 has a housing 612 which is attached to the ski by means of a fastener such as screw 613 and a holding member 615, which is attached to the ski, for receiving retainer or fastening member 613 through a bore 617 contoured to receive the fastener. A spring such as helical spring 619 is disposed in housing 612 and is located to be compressed by compression member such as nut 621 as fastener 613 is rotated. Spring 619 is compressible between shoulder 622 in housing 612 and member 621.

Retainer member 611 includes a flange 623 which extends rearwardly, and has an inclined abutment face 625 which is contoured to engage the face 607 of plate 603. Holding member 615 also has a flange 627 extending partly along the length of ski 107, and having an inclined portion with a face 629 contoured to engage the face 609 of plate 603.

Screw 613 has a flange 631 which is seated beneath the upper end wall of housing 612 of adjustment member 611, and has a head 633 which can be turned to either move nut 621 into holding member 615 to compress spring 619, or to be urged in the opposite direction to relieve the compression on spring 619.

The stiffening in the apparatus shown in FIG. 10 is accomplished by friction rather than by spacing between an adjusting member and a support plate. The apparatus is continuously adjustable.

Therefore, in the operation of assembly 601 in FIG. 10, if further stiffening of the ski is desired, screw 613 is tightened to move nut 621 towards the ski to compress spring 619. This compression urges adjusting member 611, and the face of leg 623 against face 625 of plate 603. The tension created by face 607 and face 625, and face 609 and face 629, essentially clamps plate 603 to the ski at its forward end 605, to substantially prevent bending of ski 107 between fastener 611 and the anchor between the support plate and the ski. In its most compressed condition, the ski apparatus is extremely stiff underfoot, and is particularly useful in curves made on hard snow. As fastener 613 is loosened, the compression on spring 619 decreases, and the tension on end 605 of support plate 603 becomes less and less. In its least compressed condition, the portion of ski 107 under support plate 603 is essentially bendable, and is particularly useful for skiing on loose or powder snow. There is no need for a clamp to guide support plate 603 along ski 107 as the ski bends, since the forward end of the plate is confined between the retainer 611 and the holding member 615. The friction device 601 has some useful features. First, the spring is a progressive force, the spring force increasing as the support plate between the retainer 611 and the holding member 615, increasing stiffness as the ski bends. Second, the spring provides greater friction for flexing than for counterflexing. However, the friction approaches 0 as the angle .varies. approaches 0.

Another continuously adjustable stiffening system is shown in FIG. 11. Here, a support plate 703 is attached to the ski 107 at one end, here the rear end 705, by a clamp or anchor 706, and is slidable at its other end, here the front end 707, in a clamp 709 through which the forward end can slide as the ski bends. A spring 710 is disposed in a housing 711 of a retainer 713. Housing 711, is fixed to ski 107. The housing has a rearward face 715 having a bore through which forward part 707 of plate 703 extends. An enlarged portion 719 urges end 707, and is larger than the bore in face 715 to preclude it from being removed from housing 711. Spring 710 rests against portion 719 and extends forwardly to a shoulder 721 through which a control fastener 723 extends. Fastener 723 extends through housing 711 along a longitudinal axis above ski 107, opposite plate 703.

In order to change the stiffness of the skiing apparatus shown in FIG. 11, fastener 723 can be moved to change the compression of spring 710, such as by turning its screwhead 725 with a screwdriver. At its extreme stiffness, fastener 723 is moved to completely compress spring 710. As the fastener is turned to release spring 710, the stiffness of the skiing apparatus beneath plate 703 decreases. Thus, the harder the snow and the more turns being made, the fastener 723 is adjusted to compress spring 710. As the snow gets softer, spring 710 should be decompressed to enable the control of the ski as discussed earlier.

A modification of the embodiment shown in FIG. 11 is shown in FIG. 12. Here, a support plate 753 is fixed as described above with respect to FIG. 11, and has a flange 755 attached to forward end 757, with a block 759. A housing 761 holds a spring 763 and control fastener 765, and these all function as corresponding members did in the preceding Figure. Housing 761 rests on a support 764 which is fixed to ski 107. A stop 767 extends through support 764 opposite plate 753. A space S' exists between the rearward end of stop 767 and the forward end 757 of plate 753. The stiffness of the ski is continuously adjustable by means of fastener 765 and the compression of spring 763. In addition, the ski also becomes stiff during curves when end 757 of plate 753 contacts stop 767. Stop 767 could be adjustable, and could be moved away from plate 753 so that these members do not contact each other at all, or less frequently, as for example in powder snow. Stop 767 can thus be spaced from plate 753 by an intermediate amount so that end 757 and stop 767 only contact during curves as described previously. Stop 767 could also be adjusted to contact end 757 to allow the skier to stiffen the ski under the assembly to a maximal value. Forward end 757 slides relative to ski 107 through clamps 769.

Hydraulic embodiments are shown in FIGS. 13 and 14. In these Figures, support plates 803 are fixed at one end to the ski by anchors 805. The free end 807 is slidable in a clamp 809 attached to ski 107 as the ski bends longitudinally. The free end 807 of plate 803 is attached to a piston 811 slidable in a fluid cylinder 813, which is part of a hydraulic circuit. Cylinder 811 is fixed to ski 107. The part of the cylinder chamber forward of piston 811 is connected by fluid lines to an adjustable valve 815, a selected one of oppositely directed, uni-directional valve heads 816, 817 and a manual fluid valve selector 818 connected to a fluid line for the fluid in cylinder 813 on one chamber or side of piston 811. When the system is set up as shown in FIG. 13, as the ski bends or flexes, forward end 807 and piston 811 move rapidly through the chamber in cylinder 813 since fluid is forced from the cylinder through fast flowing, one way or uni-directional valve head 816, through valve selector 818 and into the side of the cylinder chamber behind piston 811. In this configuration the ski can flex downwardly freely and easily since piston 811 encounters little resistance in its forward movement. When the downward loads which caused the ski to flex are reduced--such as the end of a turn--the ski will tend to return to its normal flex state as fluid flows from the right hand side of cylinder 813, through adjustable valve 815 and into the cylinder on the left hand side of piston 811. The rate of counterflexing will be determined by the adjustment of adjustable valve 815. The counterflex speed of the ski can thus be adjusted by the setting of valve 815, and the counterflex can be dampened.

In FIG. 14, valve selector 818 is operatively connected to uni-directional valve head 817. Now when the ski flexes, free end 807 forces piston 811 to the left, and fluid flows through adjustable valve 815; this is generally a slow flow rate depending on how valve 815 is adjusted. During counterflex, the fluid moves very quickly from the right side of piston 811, through one way valve 817 so that the piston returns quickly to the embodiment shown in FIG. 14. This is good for the free and easy counterflexing movement of the ski.

FIGS. 15A and 15B are rearward and forward parts of an exploded isometric view of a support assembly mounted on a portion of a ski 107. As shown, the support assembly comprises a support plate main member, generally 904, and a support plate slide member, generally 905. The main member 904 and its attached slide member 905, may from time-to-time be referred to as the support plate. The rearward end 903 of the support plate main member 904 is somewhat thicker than the rest of the main member allowing the forward portion of the main member to be spaced from the underlying ski 107. The rearward end of the support plate main member is provided with screw holes 902 for purposes of mounting the main member to the ski and to permit the heel portion of a ski binding to be mounted on the support plate.

The support plate main member 904 is connected to the support plate slide member 905, and to the cover plate, generally 906, by means of attachment screws, not shown, which pass through screw holes 911 and which are threaded into threaded bushings 908 attached to slide member 905.

As will be seen, the end of the support plate main member 904 opposite the rearward end 903 has a bifurcated, forked configuration with slots 910 in each of the forks and with a slot 933 positioned between the forks extending into the main member. The attachment screws referred to hold the support plate main member 904 securely to the support plate slide member 905, minimizing longitudinal movement between the two. However, in a preferred embodiment of the invention, a ribbed surface is provided at the interface between the two members, and in an especially preferred embodiment, an intermediate layer, for example, an elastomeric material, such as ebonite, is positioned as in intermediate layer between the main member and the slide member. Such a layer not only serves to assure that no longitudinal movement between the two members will occur, but provides an additional advantage in that it tends to dampen vibrations transmitted from the ski to the binding.

In the embodiment shown, the support plate slide member 905 is tapered toward the front, culminating in an abutment member 931 which serves to engage a peripheral edge of a control cam disc 920 which serves as an adjustment member or adjustment stop, as will be explained in more detail in the following. The cam disc can be pivoted about a smooth shanked fastener or special purpose screw 909 to juxtapose different peripheral surfaces to abutment member 931 thereby controlling the amount of bending or flexure of the ski, as will also be explained in more detail hereinafter. A head or cam setting lever 930 is employed to position the cam disc as desired, while resilient lugs 924 and 925 are provided to maintain the cam disc in the selected position.

A portion of the support assembly, together with the cam disc and other associated structure are positioned between a base plate 913 having lateral edges 914 and 915, and the cover plate 906, which together serve to form a protective housing for parts of the mechanism. The forward ends of the base plate act as a guide for the pivoting movement of the cam disc 920, as will be better seen in FIG. 17. (FIGS. 16-18 are enlarged from that of FIGS. 15A and 15B for the purpose of clarity). Slot 912 in the cover plate 906 accommodates movement of the forward end of the support plate which occurs during flexure of the ski.

While the back end of the support plate, specifically the rearward end of the support plate main member 903, is fixed to the ski and thus immovable, the forward end of the plate, namely, the slide member portion 905, which is supported by a slide bearing yoke, better seen in the other Figures, is free to move backward and forward, relative to the surface of the ski, thereby accommodating its flexing. The cam disc 920, in conjunction with abutment member 931 serves to control the degree of permissible movement, thereby providing a means to control the degree of flexure or stiffness which the ski is capable of experiencing.

FIG. 16 is a plan view of the support plate of FIGS. 15A and 15B, however, with the cover plate removed in the interest of clarity. The Figure shows the bifurcated forked configuration of support plate main member 904 and its attachment to support plate slide member 905 by means of attachment screws 907 inserted into the threaded bushings 908 extending through forked slots 910, the bushings forming a part of the support plate slide member. Attachment screws 907, which fasten the main member to the slide member, are better seen in FIG. 18.

The support plate slide member 905 is retained in slide bearing yoke 918, but is free to move or slide back and forth therein. As stated, the forward part of the slide member tapers to form a projecting abutment member 931 which is juxtaposed to selected peripheral sections of cam disc 920. Depending upon the clearance between the abutment 931 and the peripheral section, the cam disc either prevents, limits, or allows the essentially uncontrolled longitudinal movement of the forward end of the support plate.

As illustrated in FIG. 16, the abutment member 931 is juxtaposed to a slightly recessed peripheral section 922 of cam disc 920, thereby allowing some degree of forward movement of the abutment to accommodate flexure or bending of the ski. Should the cam disc be rotated counterclockwise to bring the recessed peripheral section 923 opposite the abutment, substantially unlimited forward travel of the abutment would be possible. However, were the cam disc to be pivoted in a clockwise direction to bring the outer periphery 921 in juxtaposition with abutment 931, essentially no movement of the slide member would be possible, in which case the support plate would act as a stiffening brace for the ski, particularly desirable where a large amount of stiffness is required, for example, during turns on hard snow. The cam disc is moved to its desired position by manipulation of cam setting lever 930. It will be seen that the resilient detents or lugs 924 and 925 engage detent recesses 926 and 927 when the cam disc is in its intermediate position, or, respectively, are located in a position abutting detent projections 928 and 929, locking the cam disc in either its slide member arresting position, or in the position permitting maximum sliding movement. The lateral edges of the base plate are also illustrated in the Figure, as is a forward portion 917 of the base plate. While a cam disc with a periphery having distinct "steps" of different radii has been described, it is also possible for the cam disc to have a periphery whose radius varies in a continuous manner.

FIG. 17 is a cross-section of a support plate along line XVII--XVII of FIG. 16. In this Figure, the front jaw of the safety ski binding can be seen attached to the cover plate 906 and to the support plate main member and support slide member, 904 and 905 respectively. The Figure also shows a ski boot in phantom positioned in the binding. Illustrated in FIG. 17 is the base plate 913 including its front portion 917 and a setback portion 916, which together with the lower portion of the base plate form an opening through which the cam setting lever 930 projects for easy access. A smooth shanked fastener in the form of a screw 909 serves the multiple functions of fastening the base plate to the ski, of serving as a pivot point for the cam disc, and to prevent any lifting or lateral movement of the forward part of the ski binding's front jaw. As previously indicated, the pivot fastener slot 912 accommodates the back and forth movement of the cover plate, which it will be remembered is attached to the main member and slide members of the support plate during flexure of the ski.

Referring again to FIG. 16, a useful feature whose function is better seen in FIG. 17, is to be found in the positioning of an elastomeric pad or plate 932 between a portion of the peripheral edge surface of the cam disc 920, and a surface of abutment member 931. As shown, the positioning of the pad can be accomplished by attaching it to the cam disc by pins located on the cam disc, over which the pad is secured by means of holes located in the latter. As is seen particularly clearly in FIG. 17, before the abutment member 931 can make contact with the peripheral edge of the cam disc 920, it must compress the elastomeric pad. The resistance of the pad to such compression exerts a desirable dampening affect which resists flexing of the ski to a degree determined by the resiliency of the pad. The pad may be disposed over one or more of the recessed peripheral sections of the cam disc to obtain the dampening function described.

FIG. 18 is a cross-section of the support plate along line XVIII--XVIII of FIG. 16 showing details of the sliding support, which allows the support plate of the invention to accommodate flexure of the ski.

FIG. 18 shows the manner in which the support plate slide member 905 is retained by a U-shaped slide bearing yoke 918, the latter being fastenable to a ski by means of fastening screws 919. The support plate main member 904, together with cover plate 906, is fastened to support plate slide member 905 by means of attachment screws 907 which extend into threaded bushings 908 forming a part of the slide member. The lateral edges 914 and 915, respectively, of the base plate enclose the slide bearing yoke 918 and their upper ends are offset inwardly at the top to function as guide rails for the cover plate 906 so that the cover plate, together with the front jaw may slide during ski flexure in relation to the base plate along the longitudinal axis of the ski. As is clear from the Figure, the lateral edges of the base plate, in conjunction with the cover plate, form a housing about a portion of the support plate assembly, protecting the parts thereof from damage and dirt which might otherwise be adventitiously introduced.

As shown in FIG. 17 and FIG. 18, the attachment screws 907 and 919 are positioned coaxially to each other. This is of considerable advantage since it makes it possible to employ the same drilling template for locating the support plate attachment holes in the ski, as is used for installing the safety ski binding screws.

In installing the support plate of the invention, the slide bearing yoke 918 is first screwed to the ski. The support plate slide member 905 is thereafter inserted into the yoke, and the base plate is placed thereon and positioned as desired. Thereafter, the rear end 903 of the support plate main member with the heel part thereon is fastened to the ski.

The forked slots 910 in the support plate main member 904, which have the threaded bushings 908 of the slide member 905 fitted therethrough, allow the positioning of main member 904 to slide member 905 to accommodate whatever length of ski boot sole is to be used in the ski binding. In this connection, boot adjustment slot 933 is provided to accommodate the shank portion of fastener 909 in instances where the ski boot sole is extremely short.

After placement of the support plate main member 904, the cover plate 906 is placed in position and smooth shank fastener 909 screwed into the ski. The front jaw is then placed on the cover plate in position and attachment screws 907 are screwed into the threaded bushings 908, simultaneously connecting support plate main member 904 to slide member 905, preventing their longitudinal movement relative to each other.

With the support plate installed as described, the cam disc 920 is adjusted to the position desired. In regard to such adjustment, as long as the support plate slide part 905 is free to slide in the slide bearing yoke 918, there will be no stressing of the ski, which will be free to flex or bend in conformity to the terrain over which it is passing. The cover plate 906 and the front jaws participate in such movement since the parts are connected together as indicated. Where the elastomeric pad 932 is present, however, such displacement will occur against the resistance of the pad which functions as a dampening element.

An elastomeric pad 934 is attached such as by some appropriate adhesive to slide member 905, to dampen the vibration between member 905 and main member 904 during skiing. Such vibration dampening means can be applied between any horizontally disposed units in the system.

FIG. 19 is a plan view of a further embodiment of the support plate shown without a cover plate, with like parts to those shown in FIGS. 15-18 having like numerical designators. As illustrated, a support plate main member 904 is fastened to a support plate slide member 935 by means of attachment screws 907, not shown, inserted into threaded bushing 908. The support plate slide member 935 is retained in slide bearing yoke 918, being free to slide therethrough, and is bifurcated at its unattached end having forks 939 and 940 located thereon. The forks are provided with fork abutment surfaces 941 and 942, respectively, adapted for juxtaposition to surface 943 to the free end 944 of pivot arm 937 which serves as an abutment or control member, or abutment stop. The opposite end of the pivot arm is attached to spring 938 whose other end is anchored, for example, to base plate 936, better seen in FIG. 20.

In this embodiment, the pivot arm or abutment stop itself cooperates in limiting the amount of longitudinal movement of which the support plate slide member is capable. In this regard, the inertial force acting on the free end 944 of the pivot arm, for instance, when the ski is running on its edge, serves to automatically pivot the arm so that the outermost radial surface 943 of the free end of the pivot arm 937 pivots to a point at which it is juxtaposed to either fork abutment surface 941 or 942, where it acts to restrain their movement. The pivoting motion acts against the force imposed by the weak spring 938; however, when the inertial force is no longer operable, the spring acts to realign the pivot arm along the longitudinal axis of the ski.

Advantageously, the juxtaposed surfaces of abutment surfaces 941 and 942, as well as the outermost radial surface 943 of pivot arm 937 having mating curved surfaces which conform to a radial arc whose center is the pivot point of the pivot arm 937.

FIG. 20 is a cross-section view of a support plate along the longitudinal centerline of FIG. 19. The construction of the pivot arm or adjustment stop is much the same as that previously described in connection with FIGS. 15 through 18, the support plate main member 904 being connected to the support plate slide member 935 by means of attachment screws 907, which engage the threaded bushing 908 disposed in the fork slots of the bifurcated end of the support plate main member 904. The slide member 935 is retained in slide bearing yoke 918, which in turn is fastened to a ski by fastening screws 919. The pivot arm 937, pivotable about the smooth shanked fastener 909 which also fastens base plate 936 to the ski, is urged into a longitudinal position, relative to the ski, by weak spring 938 anchored to the base plate 936. The Figure illustrates the thickened section of the pivot arm 944, not only adds inertial mass to the arm, but also provides the necessary surface area 943 at its end to efficiently engage the forked abutment surfaces 941 and 942, respectively.

The jaws of the binding and cover plate 906 are fastened to the assembly by attachment screws 907, as previously indicated, while the front end of the jaws are prevented from upward and lateral movement by the smooth shanked fastener 909.

If desired, provision may be made for moving the pivot arm 937 along the longitudinal axis of the support plate assembly to allow the clearance between surfaces 941 and 942 with surface 943 to be adjusted in a way allowing more or less movement of the support plate slide member 935, thus adjusting the freedom of the ski to flex.

As will be appreciated, the support plate slide member is free to slip back and forth through the slide bearing yoke 918 so long as the ski is moving in a direction of the fall line of the slope, a condition in which no stiffening of the ski adjacent to the support plate will occur. On the other hand, when the ski is moved into a turn, a condition in which inertial force acts on the pivot arm 937, the arm will swing out of the intermediate position illustrated in the Figure, the surface 943 of its free end thereupon being juxtaposed with one of the abutment surfaces 941 or 942. In this position, the movement of the slide member 935 is restrained, preventing flexing of the ski and allowing short, rapid turns to be accomplished with precision, even on hard snow.

Referring now to the preferred embodiment of the invention, FIG. 21 21 shows a ski 17 with a base plate 13 mounted thereon. A bearing yoke 18 is positioned on the base plate, being fastened to the ski by means of screw fasteners 19. A front jaw of a ski binding is connected to support plate slide member 5 by attachment screws 7 which are threaded into threaded bushings 8, better seen in FIG. 22. Extending from the support plate slide member 5 is shown a resilient finger 32, adapted to possibly engage the peripheral section of cam disc 20. Finger 32 is one of a number of fingers adapted to possibly engage the projecting peripheral sections of cam disc 20, as will be described in more detail in the following. The cam disc 20 is fastened to ski 17 by a smooth shanked fastener 9, passing through bushing 12 which serves as a swivel shaft for pivoting cam disc 20. In addition to peripheral section 22 projecting from cam disc 20, the cam disc also includes a recessed peripheral section 23, as well as other projecting sections, each of the sections playing a part in the functioning of the cam disc in its various positions, as described hereafter. The front jaw of the ski binding is free to move longitudinally with the end of the support plate slide member 5.

Not shown in the Figure, but forming a part of the embodiment, is a support plate main member which is variably fixable to support plate slide member 5 to accommodate whatever length of ski boots sold is to be used in the ski binding. The support plate main member carries the heel portion of the ski binding.

FIG. 22 is a plan view of the end of the support plate assembly according to FIG. 21, but with the front jaw of the safety ski binding removed therefrom. In the Figure is shown support plate slide member 5 from which extend a plurality of resilient fingers 31, 32, 33 and 34. Opposite the ends of the fingers is a cam disc 20 mounted to the ski by smooth shanked fastener 9 which passes through bushing 12, the cam disc being free to rotate thereabout as it is moved between its various settings, which are identified as I, II and III, as shown. The movement of the cam disc 20 between its various settings is accomplished by movement of lever 30, the cam disc being held in the selected setting by the action of detents 27 which engage recesses 26 in the cam disc. The cam disc has a number of peripheral sections projecting therefrom including sections 21 and 22, as well as an optional intermediate peripheral section 10 located between the aforesaid sections, projecting outwardly from the cam disc. The cam disc 20 also includes a recessed peripheral section 23. The rigidity of the ski is determined by the presence or absence of engagement between one or more of the peripheral sections with one or more of the fingers forming part of the support plate slide member 5.

The Figure also shows bushings 8 adapted to receive the fastener screws 7 which hold the front jaw of the safety ski binding to the support plate slide member 5. The support plate slide member 5 is free to move back and forth in a bearing yoke 18, which is carried by base plate 13, essentially T-like in its configuration, and which serves to guide the support plate slide member in its movement resulting from flexing of the ski. The two sides of the bearing yoke 18 are bent inwardly to retain the support plate slide member 5 within the yoke. The bar of the "T" has bushing 12 located therein, which serves as the swivel shaft for control cam disc 20, as previously described.

Base plate 13 is configured with upwardly bent edges 14 and 15 along its longitudinal sides, and a bridge 11 at the front end of the base on which the identifying number settings previously referred to are located. Lever 30 projects under the bridge 11, and in the Figure a recessed peripheral section 23 of the disc is juxtaposed to the fingers 32, 33 and 34, while peripheral section 22 is spaced from finger 31, the positioning described allowing an essentially unlimited forward movement of the support plate slide member 5 to accommodate bending of the ski 17.

The fingers 31, 32, 33 and 34 will desirably be made from a resilient material, particularly a resilient plastic material. While any plastic material capable of resiliently moving under the influence of engaging contact of the fingers with the peripheral sections of the cam disc is suitable for purposes of the invention, plastics such as, for example, acetal resins, which may be reinforced by glass fibers or other materials, are particularly adapted for use with the invention. One such material is the Delrin acetal resin, marketed by the DuPont company.

FIG. 23 is an isometric view of the support plate assembly of FIG. 22. The Figure illustrates the relative positioning of the components. As shown, the support plate slide member 5 moves back and forth within bearing yoke 18, which is positioned over base plate 13, plate 13 having upwardly bent edges 14 and 15 at its longitudinal sides, together with bridge 11 at the forward end thereof.

Detents 27 can be seen engaging recesses 26 on the cam disc 20, which has been moved by lever 30 into setting position I, a setting in which the recessed peripheral section 23 is juxtaposed to fingers 32, 33 and 34 extending from the forward end of the support plate slide member 5. Since finger 31 is spaced from peripheral section 22 in the setting of the cam disc shown, an essentially unlimited forward movement of the support plate slide member 5 can occur in accommodating bending of the ski 17.

FIG. 24 is a plan view of the support plate assembly of the invention, disposed in a different setting position of cam disc 20. As shown, the support plate slide member 5, which is positioned in bearing yoke 18 and provided with bushings 8 for attachment of the toe piece of a ski binding thereto, has resilient fingers 32 and 33 in operative engagement with peripheral section 22 of cam disc 20. Peripheral sections 10 and 21 of the cam disc, the presence of the former being optional, are unengaged in the position, which reflects movement of the lever 30 into the setting position of intermediate rigidity, position II of the device. The cam disc is held in the position shown by the engagement of detents 27 with corresponding recesses 26 on the cam disc 20. The bearing yoke 18 is positioned between upstanding sides 14 and 15 of base plate 13, which is also provided with bridge 11.

In setting II, as bending of the ski takes place, support plate slide member 5 is moved forwardly against the surface of peripheral section 22, causing the peripheral section to slide along the tapered inner edges of fingers 32 and 33. This movement which acts as a retardant to movement of the support plate slide member 5, forces fingers 32 and 33 laterally apart, acting to rigidify or stiffen the ski. As additional bending of the ski occurs, forcing the support plate slide member 5 to move still further in a forward direction, to the left in the Figure, the lateral spreading of fingers 32 and 33 proceeds to the point at which their outside edges engage the inner surfaces of fingers 31 and 34, respectively. The reinforcement provided by this latter engagement resists the forward movement of the support plate still further, adding to the stiffness of the ski.

FIG. 25 shows a plan view of the support plate assembly of the invention disposed in yet another positional setting. In the Figure, support plate slide member 5, positioned within bearing yoke 18 and provided with resilient fingers 31, 32, 33 and 34 extending from the forward end thereof, is positioned opposite cam disc 20 in the device's most rigid position in which the lever 30 has been moved to setting III. In this setting, fingers 31 and 34 are placed in operative contact with peripheral sections 21 and 22 respectively. Again, the cam disc 20 is held in the selected position by the engagement of detents 27 with corresponding recesses 26. While recessed peripheral section 23 plays no part in the setting III, peripheral section 10 is located opposite, but spaced from fingers 32 and 33. As shown, bearing yoke 18 is positioned between the upstanding sides 14 and 15, respectively, of base plate 13, which includes bridge 11 with the setting markings thereon.

Cam disc 20 is moved into the position shown by being pivoted about bushing 12 at the center thereof by means of pressure applied to lever 30.

Inasmuch as fingers 31 and 34 are shaped (as shown), or constructed more rigidly than fingers 32 and 33, their engagement with peripheral sections 21 and 22 results in the support plate slide member 5 encountering more resistance to forward movement as the ski attempts to bend; consequently, the ski is more rigid or stiffer than in the case of either settings I or II. Furthermore, in an optional embodiment, should the forces acting on the ski to cause bending increase beyond the ability of fingers 31 and 34 to resist the same, optionally present peripheral section 10 engages fingers 32 and 33 as the support plate slide member moves additionally forward, resulting in still further resistance to the members forward movement.

In the case of either settings II or III, as the forces tending to bend the ski are removed and the ski unbends, the fingers disengage from the peripheral sections with which they are in contact, resetting the device.

From the preceding, it can be seen that the embodiment shown in FIGS. 21-25 allows the ski to be made more rigid by moving lever 30 progressively through settings I, II and III. Such adjustment moves the rigidifying device illustrated from position I in which resistance to flexure of the ski is essentially non-existent, through setting II which provides two levels of resistance, and finally to the position of setting III, optionally providing two levels of resistance. While the stiffening influence of such settings will depend upon the nature of the fingers, particularly including their shape and dimensions, as an approximation in considering the relativity of the stiffness described, the stiffness of position I would be of a small value (about 10 kg caused by internal friction in a design as shown in the Figures); that of II would have an intermediate and higher level of resistance (35-50 kg in the depicted system); while that of setting III would provide a highest level of resistance (i.e. of about 200 kg in the system shown in the Figures). Different values of resistance can be obtained using different shapes of the fingers.

While only three settings have been described in connection with the embodiment illustrated in connection with FIGS. 21-26, other settings designed to yield still different degrees of rigidity can be provided. This result is readily accomplished merely by providing further points of engaging contact between additional fingers and corresponding additional peripheral sections on the cam disc.

FIG. 26 is a schematic drawing of a support plate assembly embodiment of the invention shown in FIGS. 21-25. In this embodiment, a stiffness control assembly 101 includes an engagement means, which can be a support plate 103, one of whose ends 105 is fixed to the ski 107 by fastening member 108, and its second end 109 is a free end which can slide in the longitudinal direction of ski 107 within guide means such as a support clamp 111. End 109 of plate 103 is shown closest to the forward end of the ski. An impedance means, designated in the Figure as an adjustable stop member 113 is also shown, the adjustable stop member being movable relative to plate 103 and ski 107 within a clamp 117, as indicated by arrow 115.

When the ski is to retain its bending ability unimpaired, the distance between the adjustable stop 113 and the free end 109 of the support plate 103 is adjusted to have a relatively high value, with no connection therebetween. Then, regardless of the degree of bending of the ski 107, plate 103 cannot engage stop 113, and no additional stiffness is imposed on the ski by the support plate 103. When, however, it is intended that assembly 101 minimize the bending of the ski, as for example when the ski is to be turned in hard snow, adjustable stop 113 is set to become engaged with the free end 109 of support plate 103 to a greater or lesser degree of bending of the ski so that there is interaction between the stop 113 and the end 109, the extent of the adjustment selected being dependent upon the snow conditions which determines the rigidity of the ski desirable under the circumstances.

For example, in a position of intermediate rigidity, as provided by the setting position seen in FIG. 24, the engaging force of two resilient fingers 32, 33 is operable against one of the projecting peripheral sections 22 of the cam disc 20. This is represented in FIG. 26 by the initial engaging connection between adjustable stop member 113 (which represents peripheral section 22) and support plate 103 which would result from the connection of the stop member and the end 109 (representing fingers 32, 33) through spring R (representing the resiliency of fingers 32, 33). As the ski undergoes more bending, however, the two fingers 32, 33 referred to could be moved laterally apart to a position in which they contact two additional resilient fingers 31, 34, the latter providing further support to the initially engaged fingers 32, 33, thus increasing the resulting rigidity. In FIG. 26, such additionally imposed rigidity is represented by the movement of support plate 103 to a position at which its end 109 also contacts spring R' (representing the resiliency of fingers 31, 34), thus imposing the rigidity effect of both springs upon the connection.

However, FIG. 26 also represents the case in which the adjustable stop 113 has been positioned in its most rigid position. Here, as shown in FIG. 25, two projecting peripheral sections of the cam 21, 22 initially engage two stiffer resilient fingers 31, 34, respectively, which are stiffer than fingers 32, 33, imposing a degree of rigidity represented in FIG. 26 by the spring R (representing the resiliency of fingers 31, 34), which in this case has a higher relative value of rigidity than in the initial position of intermediate rigidity (fingers 32, 33) described above. In an alternative construction, when the ski 107 is subjected to still greater bending, moving support plate 103 with even greater force toward the adjustable stop member 113, the end 109 corresponding to fingers 32, 33, since fingers 31, 34 are already engaged with respective peripheral sections 21, 22) moves toward the adjustable stop member 113 (corresponding to peripheral section 10) to a point which in FIG. 5 is that where an optionally provided third projecting peripheral section 10 of the cam disc 20 is brought into contact with the two resilient fingers 32, 33 described in connection with FIG. 4, increasing the rigidity still further. This additional contact is represented in FIG. 6 by the contact of end 109 (representing fingers 32, 33) with spring R' (representing the resiliency of fingers 32, 33), the point at which the cumulative effect of the resistance of both springs (corresponding to the resiliency of all four fingers) is experienced, thereby imposing maximum rigidity on the ski.

Various systems for controlling the stiffness of a ski have been described above. The skier may manually, or perhaps with the ski pole or some other device, adjust the apparatus according to the type of stiffness to be desired. In the last embodiment, this adjustment is made by the apparatus itself. The skier need not have different skiing apparatus for different types of snow or different abilities of the skier, and need not settle for a binding which is appropriate for only one type of skiing or which approximate different types of skiing but cannot adequately control the stiffness precisely for different types of skiing. Now, the skier need only adjust the apparatus for the type of stiffness desired and to participate in the skiing event. The settings can be changed as the skier desires. The invention further includes dampening means for controlling the vibration of the skis. Furthermore, in some embodiments the skier can continuously adjust the stiffness of the ski. The adjustable member could be at places other than at the forward end of the support plate, such as at the rear end, at both ends and/or in the middle. Although many embodiments are given, it should be appreciated that other variations will fall within the scope of the invention.

The invention has been described in sufficient detail to enable one skilled in the art to practice the invention, but variations and modifications within the spirit and scope of the invention may occur to those skilled in the art to which the invention pertains.

Claims

1. A system for changing the stiffness of a ski, said system comprising:

a support member having a fixed end portion attached to an upper surface of the ski and a free end portion movable longitudinally along the upper surface of the ski as the ski bends; and

impedance means operatively engageable with said free end portion as inertial forces are applied to the ski, said impedance means includes a control member mounted for pivotable movement about a fixed axis disposed transversely to said upper surface, an end portion of said control member having an inertial mass for producing lateral pivotable movement of said control member in response to inertial forces acting on said control member, said control member being biased to a longitudinally aligned position in the absence of said inertial forces, said free end portion being configured to provide free longitudinal movement of said support member relative to said control member when said control member is in said longitudinally aligned position for permitting free bending of the ski and to engage said control member when said control member is in a laterally displaced position in response to said inertial forces for limiting bending of the ski.

2. A system according to claim 1, wherein said control member is comprised of a rotatable pivot arm having a first end operatively engageable with said free end portion and a second end attached to a bias means.

3. A system according to claim 2, wherein said bias means biases the rotation of said pivot arm in order to realign the pivot arm with the longitudinal axis of said ski when the inertial force stops acting on said first end of said rotatable pivot arm.

4. A system according to claim 3, wherein said bias means is a spring.

5. A system according to claim 3, wherein the free end portion of said support member includes a pair of fork abutment surfaces.

6. A system according to claim 3, wherein said free end of said support member is in the form of a bifurcated end comprised of a pair of fork abutment surfaces adapted for juxtaposition to an outmost radial surface of said first end of said pivot arm, when the inertial force acts on said first end of said pivot arm.

7. A system according to claim 6, wherein said pair of fork abutment surfaces and said outmost radial surface of said pivot arm have mating curved surfaces conforming to a radial arc whose center is the pivot point of said pivot arm.

8. A system according to claim 2, wherein said pivot arm is rotatable about a fastener arranged transverse to the longitudinal axis of the ski.

9. A system according to claim 2, wherein said pivot arm has a thickened section at said first end to provide the inertial mass to said pivot arm and to provide surface area for efficiently engaging said free end portion.

10. A system according to claim 1, wherein said free end portion is movable along the longitudinal axis of said ski relative to said support member to vary the distance between said control member and said free end portion of said support member.

11. A system according to claim 1, wherein said control member is operatively engageable with said free end portion only while an inertial force is acting on said control member.

12. A system for changing the stiffness and vibration rate of a ski, said system comprising:

an engagement member having a fixed end portion attached to an upper surface of the ski and a free end portion movable longitudinally along the upper surface of the ski as the ski bends; and

impedance means operatively engageable with said free end portion as inertial forces are applied to the ski, said impedance means includes a control member mounted for pivotable movement about a fixed axis disposed transversely to said upper surface, an end portion of said control member having an inertial mass for producing lateral pivotable movement of said control member in response to inertial forces acting on said control member, said control member being biased to a longitudinally aligned position in the absence of said inertial forces, said free end portion being configured to provide free longitudinal movement of said engagement member relative to said control member when said control member is in said longitudinally aligned position for permitting free bending of the ski and to engage said control member when said control member is in a laterally displaced position in response to said inertial forces for limiting bending of the ski.

13. A system according to claim 12, wherein the inertial forces are established when the ski turns, and said control member is mounted to rotate when the ski turns to operatively engage said free end portion.

14. A system according to claim 12, wherein said impedance means responds to the application of only those inertial forces which exceed a certain amount.

15. A system according to claim 14, wherein said certain amount is the magnitude of the inertial force.

16. A system according to claim 12, and further including biasing means, wherein said biasing means apply a biasing force to said control member in opposition to the inertial forces, and said control member only impeding the movement of said free end portion when the inertial forces exceed the biasing force.

17. A system according to claim 12, wherein the inertial forces are centrifugal forces established when the ski turns, and said control member is mounted to rotate when the ski turns to operatively engage said free end portion.