US3752491A

US3752491A - Safety ski binding system

Info

Publication number: US3752491A
Application number: US00150974A
Authority: US
Inventors: F Fend
Original assignee: Individual
Current assignee: Marker International Co
Priority date: 1970-06-23
Filing date: 1971-06-08
Publication date: 1973-08-14
Anticipated expiration: 1990-08-14
Also published as: CS158702B2; DE2031018C3; CH540704A; FR2099146A5; DE2031018A1; ES198873U; DE2031018B2; AT306598B; ES198873Y

Abstract

A connection between the ski and the skiing boot is provided for by a separate soleplate. A plate-holding device engages the soleplate behind the heel of the boot. An abutment for the soleplate is mounted on the ski. The plate-holding device normally urges the soleplate against the abutment and releases the same in response to an overload acting in a vertical and/or horizontal direction. The abutment consists of a lever, which is pivoted to the ski on an axis which is transverse to the longitudinal direction of the ski. Said lever has a free end portion extending toward the rear end of the ski. A disc is provided on the underside of the soleplate and is adapted to be approximately coaxial to the tibia of the skier and bears on the free end portion of the lever. At least two bearing blocks are secured to the ski below the soleplate and support the soleplate before and behind the disc. The plate-holding device comprises a known, spring-loaded detent member, which engages a wedge-shaped notch at the rear end of the soleplate. The apex of said notch is rearwardly and downwardly inclined.

Description

ite States ate Fend [451 Aug. 14, .1973

[ SAFETY SKI BINDING SYSTEM [75] Inventor: Fritz M. Fend, Regensburg,

- Germany [73] Assignee: Hannes Marker,

Garmisch-Partenkirchen, Germany [22] Filed: June 8, 1971 21] Appl. No.: 150,974

[30] Foreign Application Priority Data June 23, 1970 Germany P 20 31 018.3

[52] US. Cl. 2811/1135 K [51] Int. Cl. A63c 9/00 [58] Field of Search 280/11.35 K, 11.35 T,

280/11.35 Y, 11.35 R, 11.35 A, 11.35 E, 11.35 C, 11.35 D

Primary Examiner-Kenneth 1-1. Betts Assistant Examiner-Reinhard Eisenzopf Attorney-Fieit, Gipple & Jacobson [5 7] ABSTRACT A connection between the ski and the skiing boot is provided for by a separate soleplate. A plate-holding device engages the soleplate behind the heel of the boot. An abutment for the soleplate is mounted on the ski. The plate-holding device normally urges the soleplate against the abutment and releases the same in response to an overload acting in a vertical and/or horizontal direction. The abutment consists of a lever, which is pivoted to the ski on an axis which is transverse to the longitudinal direction of the ski. Said lever has a free end portion extending toward the rear end of the ski. A disc is provided on the underside of the soleplate and is adapted to be approximately coaxial to the tibia of the skier and bears on the free end portion of the lever. At least two bearing blocks are secured to the ski below the soleplate and support the soleplate before and behind the disc. The plate-holding device comprises a known, spring-loaded detent member, which engages a wedge-shaped notch at the rear end of the soleplate. The apex of said notch is rearwardly and downwardly inclined.

7 Claims, 4 Drawing Figures PAIENIEnAus 14 I975 SHEET 1 BF 2 INVENTOR:

PATENIEIJMI: 14 ms SHEET 2 BF 2 WM w SAFETY SKI BINDING SYSTEM The present invention relates to a safety ski binding system, in which a connection between the ski and the skiing boot is provided for by a separate soleplate and which comprises a plate-holding device, which engages the soleplate behind the heel of the boot, and an abutment for the soleplate, which abutment is mounted on the ski, and the plate-holding device normally urges the soleplate against the abutment and releases the same in response to an overload acting in a vertical and/or horizontal direction.

Compared to the known, commercially available safety ski bindings, in which the skiing boot is held by safety release elements directly engaging the sole of the boot, this safety ski binding system has the advantage that the forces required for a release are independent of the shape and elasticity of the sole of the boot because the safety release elements engage the additional soleplate. Besides, the adjustment of a given force required for a release is simpler and faster because there is only a single release element for twisting and forward falls.

A known ski binding which has been described as a plate binding has the important disadvantage that the soleplate may become seized between the relatively Widely spaced points where it is gripped. Such seizing may occur, e.g., when the ski moves through a depres sion. At that time, the forces by which the plate is re tained on the ski may increase so highly'that any dangerous twisting movement which may be performed does not result in the required release so that the risk of a dangerous torsional fracture of the tibia is greatly increased. On the other hand, the retaining forces are often smaller than required during normal skiing if the required margin of safety is taken into account.

It is an object of the invention to provide a safety ski binding system which combines the advantages of the known ski bindings but is free of their disadvantages.

In a safety ski binding system, in which a connection between, theski and the skiing boot is provided for by a separate soleplate and which comprises a plateh olding device,-which engages the soleplate behind the heel of the boot, and an abutment for the soleplate,

which abutment is mounted on the ski, and in which the.

platerholding device normally urges the soleplate against the abutment and releases the same in response to anoverload acting in a vertical and/or horizontal direction, this object is accomplished in that the abutment consists of a lever, which is pivoted to the ski on an axis which is transverse to the longitudinal direction of the ski, said lever has a free end portion extending toward the rear end of the ski, a disc is provided on the underside of the soleplate and approximately coaxial to the tibia and bears on the free end portion of the lever, at least two bearing blocks are secured to'the ski below the soleplate and support the soleplate before and behind the disc, the plate-holding device comprises a known, spring-loaded detent member, which engages a wedge-shaped notch at the rear end of the soleplate, and the apex of said notch is rearwardly and downwardly inclined. In this arrangement, the soleplate is normally held in position on the ski but under the action of forces which are dangerous to the skier's leg the skiing boot and the, plate can always detach from the ski equally well and with the same ease regardless of the direction of said forces. Even when the ski is exing system shown in FIG. I,

tremely deflected by some external influence, a release of the soleplate will not be prevented because the distance between the points where the plate is gripped is minimized.

In a development of the invention, it has proved particularly desirable to provide a disc which is round and a pivoted lever which at its free end has a recess, the edge of which normally embraces part of the periphery of the disc. As a result, the soleplate and the skiing boot are freely rotatable relative to the ski during a twisting fall of the skier, and during normal skiing the controlling forces exerted by the skiers leg are transmitted to the ski positively and directly in such a manner that the safety release element is by-passed.

To facilitate the application of the soleplate to the ski and the rotation of the soleplate to its correct position, in which the soleplate is parallel to the ski, when the skis are reapplied, e.g., after a fall of the skier, it has proved desirable to provide a centering plate, which is secured to the ski on that side of the disc which is opposite to the lever, and which centering plate at that end which faces the disc has a recess, which has the shape of an arc of a circle having the same radius at the disc, and the edge of which embraces the disc with a clearance.

The sum of the frictional forces between the soleplate and its bearings'assists the resistance presented by the spring. To prevent a change of that sum when the weight of the skier is shifted, the bearing blocks are preferably spaced equal distances apart from the axis of rotation of the plate. It is desired to compensate an increase of these frictional forces even when the plate has been lifted from the rear bearing block. For this purpose, the included angle of the wedge-shaped notch may, in accordance with a feature of the invention, 'decrease continuously in a downward vertical direction.

If a retaining element is desired to provide for an additional connection between the ski and the soleplate, this additional connection may be provided for by two elastic strips, which are disposed below the soleplate and on both sides of the disc and extend parallel to the longitudinal direction of the ski, and each of said strips may have one end which is secured to the ski and another end secured to the underside of the plate, in such a manner that that end of each strip which is nearer to the disc is secured to the ski. The ends of the elastic strips may be articulatedly connected to the ski and to the soleplate and the centering plate may serve as one of the means for securing the strips to the ski.

An embodiment of the invention will now be described more fully and by way of example with refer ence to the accompanying drawings, in which.

FIG. 1 is a central longitudinal sectional view showing the safety ski binding system,

FIG. 2 is a top plan view showing the safety ski bind- FIG. 3 is a transverse sectional view taken through the safety ski binding system of FIG. 1 and taken on line III-III thereof, and

FIG. 4 shows the safety ski binding system in a position at the upper limit of its elastic range.

The safety ski binding system which is shown com prises a channel-shaped soleplate 1 (see particularly FIG. 3), which has upstanding flanges 2. The skiing boot 3 is secured on top of the soleplate 1 between the flanges 2 thereof so that the boot can be only arbitrarily detached from the soleplate. For this purpose, a known heel tightener lever 4 is provided, which is pivoted to the rear end of the plate 1 and comprises tightener cables 5, which are secured to the flanges 2 ofthe soleplate 1, and a toe iron 6, which has a horizontal arm 7 engaging the toe portion of the sole of the skiing boot. The tightener lever 4 is operable to force the skiing boot against the toe iron 6. To enable a fixation of different sizes of skiing boots to the soleplate l, the toe iron 6 is mounted on the flanges 2 of the plate 1 in such a manner that it is adjustable in the longitudinal direction of the plate 1. For this purpose the toe iron comprises two rearwardly extending arms 8, which engage the flanges 2 of the soleplate on the outside. Each of the arms 8 is provided on the inside with vertical serrations or rough portions 9 and is also provided with two horizontally extending slots 10. The forward portions of the flanges 2 of the soleplate l are provided on the outside with a corresponding serration or rough portion 11. The toe iron 6 can be secured in the desired position by means of four threaded bolts 12, which are secured in the flanges 2 of the soleplate and extend outwardly through the slots 10 in the arms 8, and by nuts 13, which are respectively threaded on said bolts. An adaptation to the thickness of the sole is generally required only once. For this purpose, the horizontal arm 7 of the toe iron 6 is bent in an upward or downward direction to the desired extent. An adaptation to heels having different heights is enabled in that the tightener cables 5 of the heel tightener 4 can be secured to the rear end portions of the plate flanges at different points. For this purpose, each plate flange 2 is provided with four bores 14.

In the normal position shown in FIGS. 1 and 2, the soleplate l is supported by three bearing blocks 15, which are secured to the ski 16. These bearing blocks are screw-connected or adhesively bonded to the ski by means which are not shown. At least the upper surface of the bearing blocks consists of low-friction material, such as teflon.

Two substantially channel-shaped bearing brackets 17 are secured on top of the ski 16 below the soleplate l and have upstanding flanges. A pivot 18 is nonrotatably held between the flanges of each of said bearing brackets. In accordance with the invention, a lever 19 is pivoted on said pivots. The lever 19 comprises two supporting arms 20, which normally extend in the longitudinal direction of the ski toward the rear end of the ski, and a crosspiece 21 at the end of the supporting arms. A recess 23 (see particularly FIG. 2) is provided on that side of the crosspiece 21 which faces the rear end of the ski. The edge of said recess has a portion defined by an arc of a circle and two portions defined by straight lines which tangentially merge into the arcuate portion. The soleplate 1 is provided with a circular disc 24, which enters the recess 23 so that the soleplate 1 bears on the lever 19 in the direction toward the tip of the ski. The circular disc 24 is riveted to the underside of the soleplate 1 adjacent to the axis of the tibia and at its peripheral surface is formed with a closed annular groove 25, which has a rounded cross-section and is in mating contact with the also rounded edges of the recess 23 of the lever 19.

A plate-holding device 30, which is known and for this reason will not be described more fully, is screwconnected to the ski 16 behind the soleplate l. The plate-holding device 30 comprises a detent member 31, which is biased by a spring 36. The detent member 31 consists of a balland engages a wedge-shaped notch 32, which is formed in a bracket 33, which is secured by screws 34 to the rear end of the plate. To ensure a rigid connection of the bracket 33 to the soleplate 1, the bracket is provided with a slot in which the soleplate is engaged. The wedge-shaped notch 32 is disposed at the rear end of the bracket and has an apex 35 which is rearwardly and downwardly inclined (see FIG. 1) so that in the normal position the detent member 31 lies in the upper portion of the notch. When the binding is ready for skiing, the spring-biased detent member 31 urges the disc 24 of the soleplate against the lever 19, which constitutes a forward abutment.

To prevent a lifting of the forward end of the soleplate 1 from the ski 16 when the soleplate is parallel to the ski, a Z-shaped angled holding-down member 40 is mounted on the ski between the forward bearing blocks 15. One flange 41 of the holding-down member 40 is screw-connected to the ski. The upper flange 42 of the member 40 is spaced from the surface of the ski and extends toward the tip of the ski. As is apparent from FIG. 2, the upper flange 42 is pointed forwardly and is rounded in the horizontal and vertical directions. A tongue 43 has been struck from the soleplate 1 and bent downwardly and reawardly engages the underside of the tip of the upper flange of the holding-down member (see particularly FIG. 1).

Two elastic strips 45 are provided, each of which has one end which is articulatedly connected to the ski and another end which is articulatedly secured to the underside of the soleplate so that the soleplate remains connected to the ski 16 also when the plate-holding device 30 has been unlocked because the detent member 31 no longer engages the notch 32 in the soleplate. The elasticity of these retaining strips 45 is so large that the movement performed by the soleplate 1 when the safety ski binding system is released is not appreciably hindered.

The manipulation of the binding system is extremely simple. The skier applies the skiing boot to the soleplate 1, which has normally been secured to the ski in the correct manner. The skier then pushes the toe portion of his boot under the horizontal arm 7 of the toe iron 6 and thereafter applies the roller provided at the lower end of the heel tightener 4 onto the heel of the skiing boot and swings up this lever beyond its dead center position so that the upper end of the lever engages the upper of the skiing boot at a point above the heel of the ski boot. The skiing boot 3 is now firmly secured to the plate 1. When the skiing boot is to be disconnected from the plate, it is sufficient to swing back the tightener lever 4 beyond its dead center position, e.g., by means of a skiing boot.

If during skiing a force which is directed upwardly and at right angles to the surface of the ski acts on the skiers leg and on the soleplate l and said force exceeds the initial stress of the spring 36 which biases the detent member 31, the rear end of the soleplate 1 will swing upwardly about the forward bearing blocks 15. As is clearly apparent from FIG. 3, the lever 19 which serves as a forward abutment for the soleplate l swings also upwardly because the forward pressure applied by the detent member 31 continues to force the disc 24 into the recess 23.

If the force does not increase to the value of the set force required for a release or if it acts only as a shock and decreases before the detent member 31 has left the notch 32, the spring force aided by the weight of the skicr forces the soleplate I back to its initial position and the lever 19 also swings back to its normal position.

If a force which is vertically upwardly directed and which is dangerous for the skier's leg acts on the skiing boot not only as a shock, the soleplate 1 will swing first to the position shown in FIG. 3, as has been described hereinbefore. As the pivotal movement of the soleplate is continued, the detent member 31 leaves the notch 32 so that the soleplate 1 can move substantially freely relative to the ski and can disengage the abutment lever 19 because the pressure from the rear is suddenly eliminated at this time. The elastic strips prevent a complete disconnection of the ski from the skiers foot.

Under the action of forces which are directed transversely to the longitudinal direction of the ski and which exceed the initial stress of the spring 36, the plate swings about the axis of the disc 24 so that the latter turns in the recess 23 of the lever 19. The detent member then runs up on one side of the notch 32. If the force decreases before the detent member 31 has disengaged the notch 32, the spring 36 will return the detent member 31 to its central position into the notch 32 so that the soleplate 1 also swings backs to its normal position.

If an excessive force in a direction which is transverse to the longitudinal direction acts not only as a shock, the plate 1 will turn in the manner described hereinbefore until the detent member 31 leaves the notch after a predetermined elastic movement, which is determined by the lateral extension of the sides of the notch. The plate can then also move freely relative to the ski.

It will be understood that the action of a force on the heel of the skiing boot in an upwardly inclined direction, e.g., in the case of a diagonal fall of the skier, the horizontal and vertical movements of the plate will be superposed and will reliably cause the same to be released when the force reaches a value which is dangerous to the skiers leg.

When the soleplate has been released, e.g., after a fall, and the skier desires to re-apply the ski, he holds the skiing boot 3 an the soleplate 1 connected thereto to extend transversely to the ski 16 and applies the soleplate to the ski so that the disc 24 is received in the recess 23. The skiing boot 3 together with the plate 1 is then turned so that the detent member slides on the corresponding oblique outside surface of the notched bracket 33 until the detent member 31 falls into the notch 32.

To facilitate the application of the skis, a centering plate 46 is secured to the ski 16 on that side of the disc 24 which is opposite to the lever 19. At that end of the centering plate 46 which faces the disc 24, the centering plate 46 has a recess 47, which is defined by an arc of a circle having approximately the same radius as the disc. The clearance between the recess 23 in the lever 19 and the recess 47 in the centering plate 46 is so large that the disc 24 is embraced with a clearance when the soleplate l is applied to the ski 16.

To ensure that a shifting of the weight of the skier will not result in a change of the torsional friction between the soleplate 1 and the bearing blocks 15, which torsional friction is to be overcome during a release in response to a twisting or diagonal fall, the bearing blocks are spaced equal distances apart from the axis of rounion olthc plate, more particularly, of the disc. ln this case, the sum of the torsional friction forces acting at the bearing blocks will remain constant as long as the plate rests on both bearing blocks. In order to maintain this friction constant even when the soleplate has been lifted from the rear bearing block, the notch is designed so that its wedge angle decreases downwardly so that an increase of the friction can be compensated by a decrease of the spring bias applied to the plate-holding device until the plate is released.

What is claimed is:

1. A safety ski binding comprising a soleplate adapted to receive the skiing boot of a skier, said soleplate having a wedge-shaped notch associated with the rear end of the soleplate, an abutment mounted on the ski comprising a lever having one end pivoted to the ski on an axis which is transverse to the longitudinal direction of the ski and having another end which is unattached to the ski and extends toward the rear of the ski, a disc mounted on the underside of the soleplate and adapted to be approximately coaxial to the tibia of the skier, bearing means mounted on the ski below the soleplate such that the soleplate can bear on the bearing means in front of and behind the disc, and means adapted to engage the rear of the soleplate and to urge the disc against the unattached end of the lever and to release the soleplate in response to an overload force, said means comprising detent means and spring means adapted to urge said detent means against the wedgeshaped notch.

2. The safety ski binding of claim 1 in which the disc is round and the unattached end of the lever has a recess which normally engages part of the periphery of the disc.

3. The safety ski binding of claim 2 and further comprising a centering plate mounted on the ski on the opposite side of the disc from the lever and in which the centering plate has a recess facing the disc having part of the arc of a circle having the same radius as the radius of the disc and in which the recess of the centering plate embraces the disc and is spaced therefrom.

4. The safety ski binding of claim 1 in which the bearing means in front of the disc compriSe bearing blocks sapced equal distances apart from the axis of rotation of the soleplate.

5. The safety ski binding of claim 1 in which the wedge-shaped notch has a wedge angle which is continuously decreasing in the downward vertical direction.

6. A safety ski binding of claim 3 and further comprising retaining means providing an additional connection between the ski and the soleplate, said retaining means comprising two elastic strips positioned below the soleplate and on both sides of the disc and extending parallel to the longitudinal direction of the ski, each of said strips having one end mounted on the ski and the other end mounted on the underside of the soleplate in such a manner that the end of the strip which is nearer to the disc is mounted on the ski.

7. The safety ski binding of claim 6 in which the ends of the elastic strips are articulately connected to the ski and to the soleplate and in which the centering plate serves as one of the means for securing the strip to the ski.

Claims

1. A safety ski binding comprising a soleplate adapted to receive the skiing boot of a skier, said soleplate having a wedge-shaped notch associated with the rear end of the soleplate, an abutment mountEd on the ski comprising a lever having one end pivoted to the ski on an axis which is transverse to the longitudinal direction of the ski and having another end which is unattached to the ski and extends toward the rear of the ski, a disc mounted on the underside of the soleplate and adapted to be approximately coaxial to the tibia of the skier, bearing means mounted on the ski below the soleplate such that the soleplate can bear on the bearing means in front of and behind the disc, and means adapted to engage the rear of the soleplate and to urge the disc against the unattached end of the lever and to release the soleplate in response to an overload force, said means comprising detent means and spring means adapted to urge said detent means against the wedge-shaped notch.