Safety binding of a boot on a ski

The present invention relates to a safety binding of a boot on a ski comprising two lateral clamps (4) movably mounted under the action of an elastic member (28) parallel to the plane of the ski (3) between a closed position in which the clamps coact with the sole of the boot and an open position. Each clamp (4) is connected to one end of a longitudinally slidable strip (45) by means of articulatedly interconnected rods. The other end of the strip coacts with a crank (29-30) subjected to the action of the resilient member, whereby this crank has two stable positions corresponding to the respective open and closed positions of the clamps.

The present invention relates to a safety binding of a boot on a ski with 
lateral clamps, that is, in which two lateral clamps are movably mounted 
parallel to the plane of the ski, under the influence of a resilient 
member, between a closed position in which they cooperate with the sole of 
the boot and an open position in which the latter is completely freed. 
The principle of bindings with lateral clamps has been known for a number 
of years, particularly from French Pat. Nos. 1,411,638 and 2,021,237, but 
has not until the present been sufficiently satisfactorily and safely 
embodied to be successfully commercialized. Certain improvements have been 
made for example to avoid the need for the user to reset the binding once 
the latter has been voluntarily opened or in the case of a fall, as 
described in French Pat. Nos. 2,332,773 and 2,445,730, or to improve the 
disengagement of the boot when opening the safety binding, as described in 
French Pat. No. 2,420,358. 
Nevertheless, the known bindings with lateral clamps all have one or more 
of the following drawbacks: the possibility of insufficient lateral 
disengagement from the boot, the latter being hindered by the presence of 
the clamps even when these are in open position, too great complication of 
the system and accordingly a non-competitive sales price, the need to use 
a special plate to fix to the sole of the boot, etc. Finally, all these 
known bindings use movable members such as wedges, inclined members, etc., 
which are in frictional contact with each other, which tends to pose more 
or less long-term problems when wear begins to impede the normal operation 
of the movable members. 
Accordingly, the object of this invention tending to alleviate 
simultaneously all of the preceding disadvantages, consists in a binding 
of the type described above and which is characterized by the fact that 
each lateral clamp is carried by an arm pivotally mounted on the ski and 
is connected to one end of a longitudinally slidable strip by means of 
articulatedly interconnected rods, and by the fact that the other end of 
the strip coacts with a crank subjected to the action of a resilient 
member, whereby this crank has two stable positions corresponding to the 
respective open and closed positions of the clamps. 
According to a first embodiment of the invention, the crank is constituted 
by an elbowed member of which one end coacts with the strip and the other 
end is connected by an articulated rod to a piston subjected to the action 
of a resilient member, this element being pivoted by its elbowed portion 
on an actuating lever. 
According to a second embodiment of the invention, the crank is constituted 
by a casing containing the resilient member, which has a portion pivoted 
on a transverse axle fixed to a support secured to the ski and a portion 
articulated to an actuating lever, the two portions forming the casing 
sliding longitudinally the one in the other. 
The safety binding according to the invention may moreover comprise 
automatic closure means acting on the crank of said binding.

Referring first to FIGS. 1 to 4, the safety binding comprises two base 
plates 1, 2 secured on a ski 3 and between which are mounted two lateral 
clamps 4, 4' laterally movable under the influence of a resilient member 
contained in a casing 5 secured to the ski, the resilient member being 
adapted to be actuated by a lever 6. Each clamp 4, 4' comprises in the 
embodiment illustrated by way of example a portion 7, 7' upwardly inwardly 
inclined and forming with the plane of the ski an acute angle that 
increases from front to rear so as to impart to this portion a somewhat 
helical appearance. The minimum angle .alpha. may be of the order of about 
30.degree., while the maximum angle .beta. may be of the order of about 
60.degree.. 
According to a modification shown in phantom line in FIG. 1, each clamp 4 
can have a hollow medial portion 7a leaving but two external portions 7b, 
7c somewhat forming claws. 
The ski boot 8 adapted to coact with the clamps described above comprises a 
sole 9, whose medial portion 10 has lateral edges 11, 11' forming on each 
side of the sole a ramp making with the plane of the latter an acute angle 
increasing from front to rear and giving it a shape corresponding to that 
of the space between the clamps 4, 4' in closed position. Thus, in the 
operative position shown in FIG. 1, the clamps 4, 4' exactly mate with the 
lateral ramps 11, 11' of the medial portion 10 of the sole 9 of the boot 
8. 
Moreover, to ensure easy lateral disengagement of the boot 8 when the 
clamps are in open position, either as the result of a fall, or 
deliberately, the sole 9 also has two transverse channels 12, 13 
respectively forwardly and rearwardly bounding the medial portion 10. The 
rear end of this medial portion 10 also has a recess 14, disposed on the 
longitudinal axis of the sole and which is adapted to coact, in the 
operative position, with a centering cone 15 secured to the upper plate 2 
of the binding, to the rear of the lateral clamps 4, 4' and on the medial 
longitudinal axis of the ski. 
The first embodiment of actuating device for the lateral clamps 4, 4' will 
now be described with reference to FIGS. 5-8. The clamps 4, 4' whose shape 
seen from above is conical, opening rearwardly, comprises also hook 
portions 7, 7' of the clamps 4, 4' clamping in this closed position the 
edges of the medial portion of the sole of the boot. 
As shown in FIGS. 5 and 7A, a strip 19 is longitudinally slidably mounted 
between the two arms 17, 17' carrying the clamps 4, 4', the sliding 
movement being centered by a pin 20 fixed to the plate 1 coacting with a 
longitudinal slot provided in this strip 19. The forward end of this strip 
19 is connected to the lateral clamps 4, 4', more particularly to their 
horizontal portions 16, 16', by means of two pairs of rods 22, 23; 22', 
23'. Each pair comprises a first rod 22, 22' whose one end is pivoted to 
the end of the strip 19, the other end of this rod 22, 22' being itself 
pivoted on a second rod 23, 23', which is pivoted on the horizontal 
portion 16, 16' of the jaw 4, 4'. The various pivots are provided by 
respective vertical pivotal axles 24, 24'; 25, 25'; 26, 26'. Finally, the 
outer edge of each second rod 23, 23' is in contact with a roller 27, 27' 
secured to the plate 1 and provided with a ring that turns so as to guide 
and promote the movement from one position to the other. 
As shown in FIGS. 6, 7B and 8, the strip 19 is connected by its rear end to 
a resilient member constituted here by a spring 28 fixedly mounted 
relative to the ski, longitudinally behind said strip 19. This connection 
is provided by a crank 19 constituted in this first embodiment by an 
elbowed member whose one end coacts with strip 19 and whose other end is 
connected by a rod 30 to a piston 31 fixed to spring 28. More 
particularly, and as shown in FIG. 7B, a transverse axle 32, secured 
between the corressponding ends of two cranks 29, 29' laterally disposed 
parallel to each other, coacts with the channel formed between two 
transverse projections 33, 33' carried by the rear end of strip 19. 
Likewise, each of the two cranks 29, 29' is connected to the piston 31 by 
a rod 30, 30' a transverse axle 34 being secured to the pivot between the 
rods 29, 29' and the rods 30, 30' and a transverse axle 35 whose ends 
serve as pivots for the rods 30, 30' coacts with said piston 31. A guide 
rod 36 which is moreover longitudinally secured by one of its ends to the 
piston 31, passes through the spring 28 and enters freely at its other end 
within an adjustment screw 37, adapted to regulate the resilient force of 
spring 28 by screwing and unscrewing the latter in the wall of casing 5. 
Finally, the transverse axle 38 connecting the elbowed portions of the two 
parallel cranks 29, 29' is pivoted in the lateral wall of casing 5. 
The connection mechanism between strip 19 and resilient member 28 enables 
via cranks 29, 29' defining two stable positions corresponding to the 
respective open and closed positions (FIGS. 6 and 8) of the lateral clamps 
4, 4'. 
As shown in FIG. 1, the manipulable lever 6 is pivotally mounted about the 
ends of axle 38 outside casing 5, and is pierced on each side by a 
slightly arcuate opening 40 in which move the ends of the transverse axle 
34 serving as pivot between the two cranks 29, 29' and the two rods 30, 
30'. 
The binding of the boot 8 on ski 3 is achieved by placing the former 
between the open lateral clamps 4, 4' such that the boot is centered 
thanks to the centering cone 15 coacting with the corresponding recess 14 
provided at the rear of the medial portion 10 of boot 9. It then suffices 
to pull on the tension lever 6 to raise it and thereby to effect reversal 
of the position of the cranks 29, 29' which displaces rearwardly the strip 
19 (see FIG. 8) thereby to close clamps 4, 4' on the medial portion 10 of 
the sole 9 of the boot 8. 
According to a modification shown in phantom line in FIGS. 2 and 3, the 
upper edge of the portion 7 of each clamp 4 may have two open recesses 50 
approximately square or rectangular in shape, and whose lateral internal 
walls are inwardly flared, with slopes of about 45.degree.. These recesses 
50 are adapted to coact in operative position with cleats 51 of a shape 
corresponding to those of the recesses. In this modification, the 
torsional force in case of a fall is better transmitted to the clamps, and 
moreover the centering of the boot is improved. 
The arrangement of the connection of strip 19 to resilient means 28 by 
means of a crank system permitting movement of the bearing axis of the rod 
connected to said resilient member, provides a lever arm which changes 
gradually, thus progressively decreasing the moment of force necessary to 
pass from the open position to the closed position and vice versa. The 
opening or closing of the clamps is thus automatically effected 
immediately after passing the equilibrium point of the crank (reversal 
point). It will be seen that the spring 28 is less compressed in the 
operative position (FIG. 8) than in the open position (FIG. 6) and 
accordingly less mechanically stressed, which tends to improve its 
longevity. 
Moreover, the system of rods 22, 22'; 23, 23' to effect connection between 
the forward end of strip 19 and the clamps 4, 4' permits maximum opening 
of the latter for a very small longitudinal movement of the strip 19 and 
thus of spring 28. This is important to permit complete disengagement of 
the boot when the clamps are in the open position, either by deliberate 
manipulation of lever 6 by lowering it, for example by pushing the point 
of the ski pole into recess 41 provided for this purpose at the upper end 
of lever 6 and pushing downwardly on the latter, or because of a fall that 
actuates the safety system. Indeed, the length of the medial portion 10 of 
the sole 9 being less than the minimum distance between the clamps 4, 4' 
in the open position, the boot may enjoy a rotation of 90.degree. to each 
side of the ski above the clamps 4, 4' thanks to the presence of the 
transverse channels 12, 13 forwardly and rearwardly delimiting this medial 
portion 10, which permits disengagement of the boot in no matter what 
position. 
Thus, the use of articulated rods permits achieving a longer lifetime for 
the device, friction being substantially reduced with respect to known 
systems. 
In this first embodiment of binding according to the invention, it is also 
possible to provide a system for automatic donning, making it unnecessary 
for the user to manipulate the lever. Contrary to known systems, which are 
based on the retention provided by the resilient member, the automatic 
closing means shown in FIGS. 9 and 10 is adapted to push lightly the strip 
19 to reverse the tension position thanks to the presence of the crank. 
This automatic closure means may be comprised for example by a lever 42 
articulated about a transverse axis 43 fixed relative to the ski and 
having a heel 44 coacting in the open position of the clamps with the 
forward transverse projection 33 of strip 19 (see FIG. 9). To lock the 
binding automatically, it then suffices to lower the lever 42 by applying 
the heel of the boot 8 to its forward free end. This movement produces 
pressure by heel 44 against the transverse projection 33 and thus the 
rearward displacement of the strip 19 (see FIG. 9), which has the result 
of swinging the structure to the closed operative position with the strip 
19 in its rearwardly urged position (see FIG. 10). 
The binding shown in FIGS. 11 and 12 is a modified embodiment of the 
actuating means for the clamps described above with reference to FIGS. 5 
to 8. 
In this modification, the sliding strip 45 is connected to arms 46, 46' 
carrying the clamps 4, 4' by means of two pairs of rods, more particularly 
to forward portions 47, 47' of these arms whose lateral edges comprise the 
clamps 7b, 7c. Each pair of rods comprises a straight rod 48, 48' 
articulated to the forward end of strip 45 and a right-angle-elbowed rod. 
This rod 49, 49' is pivoted at the level of its albowed portion about a 
pin 50a, 50a' secured to base plate 1. It is moreover pivoted by one of 
its ends to the forward end of straight rod 48, 48' on the one hand, and 
by its other end to a pin 50b, 50b' secured to the forward portion 47, 47' 
of clamps 4, 4' on the other hand, this pin 50b, 50b' coacting more 
particularly with a longitudinally elongated opening 51 in the end of said 
elbowed rod 49, 49', thereby to permit lateral opening of the clamps 4, 4' 
under the influence of forward longitudinal translational movement of 
strip 45. In this modification, the regions of friction are thus decreased 
which improves the quality of operation of the mechanism and its lifetime. 
As to the rest, the operation of this embodiment is the same as that 
previously described, the corresponding parts having the same reference 
numerals as in the embodiment of FIGS. 5 to 8. 
Moreover, in this modification is shown an adjustable stop 52 which may be 
provided forward of the clamps 4, 4' of the binding. This adjustable stop 
comprises a block 53 affixed to the forward end of a leaf 54 slidably 
longitudinally mounted in an axial opening 55 provided below the base 
plate 2' of the binding. This leaf 54 is provided with teeth 56 adapted to 
coact with a screw member 57 actuable from the outside so as to fix the 
longitudinal position of the adjustable stop. Thus, this stop has on the 
one hand the advantage of facilitating for the skier putting on the 
binding while determining the forward position against which must be 
placed the forward end of the boot sole and permits on the other hand, 
thanks to the external aerodynamic form of the block 53 to deflect snow to 
the sides and avoids accumulation of the latter against the toe of the 
boot. 
Another modification illustrated in FIGS. 13 and 14 is distinguished from 
the preceding in that it comprises moreover an automatic closure or 
"step-in" device for the opened clamps by placing in operative position 
the ski boot (not shown) on the binding. In contrast to the embodiment of 
FIGS. 9 and 10 requiring the position of a particular supplemental closure 
member, there is used in the modification of FIGS. 13 and 14 the 
horizontal return movement of the ski brake ("stopper"). Thus, the two 
lateral arms 56, 56' of the stopper are secured for rotation on two 
cylinders 57, 57' pivotally mounted on their axes in the side walls of 
casing 5, each cylinder having an actuating pin 58, 58' perpendicular to 
the axis of said cylinder 57, 57'. Thus, in the non-operative position of 
the binding (not shown), that is to say when the clamps 4, 4' are open and 
the strip 45' is in forward position, the stopper is in its active 
position with the forward portion 59 of the latter in raised position, as 
shown in phantom line in FIG. 13, and the arms project below the ski. When 
the skier again puts on his skis, he then presses with his boot on this 
forward portion 59 of the stopper to return the latter to its illustrated 
horizontal inactive position, which rotates the transverse cylinders 57, 
57' counterclockwise, whereby the pins 58, 58' enter into contact with 
transverse wings 60, 60' on the strip 45' and push the latter rearwardly 
to swing the crank 29-30 and thus to close the clamps 4, 4'. 
In the embodiment shown in FIGS. 15 and 16, the crank assembly constituted 
by rods in the embodiments previously described is replaced by another 
arrangement in which the actuating lever 61 plays the roll of the elbowed 
rod and the crank system is provided by the fact that the casing 62 
containing spring 61 of the binding is pivotally mounted. 
More particularly, the pivoting casing-spring 62 is comprised of two parts 
63, 64, forward part 63 being slidably displaceable on rear part 64, so as 
to act as a piston to compress spring 28, the force of the latter being 
adjustable by means of an adjustment screw 65 accessible from the rear of 
the device. 
The rear portion 64 of the casing-piston 62 is pivotally mounted on 
transverse axles 66, 66' in two lateral walls 67, 67' secured vertically 
on the upper surface of ski 3. As to the rear portion 63 of this casing 
62, it is pivotally mounted on transverse axles 68, 68' in the lateral 
walls of the lever 61, the latter being pivotally mounted on axles 69, 69' 
in the fixed lateral walls 67, 67' of ski 3. 
In FIGS. 15 and 16 is shown the position of the device corresponding to the 
operative position with closed clamps. When the lever 61 is deliberately 
pushed downwardly, or in case of an opening of the clamps resulting from a 
fall for example, then the casing-spring 62 moves simultaneously 
downwardly with lever 61 by pivoting on axles 66, 66' and axles 68, 68' 
connecting the lever 61 to the casing 62 follow the arc of a circle, which 
compresses the spring 28 and reverses the crank; thus the transverse pin 
32 on the lower end of lever 61 tends to press the actuating strip 45 of 
clamps 4, 4' forwardly in cooperation with the projection 33 on the strip 
45 at its rear end. 
Finally, the embodiment schematically shown in FIGS. 17 and 18 is 
distinguished from the preceding ones by the fact that the resilient 
member is disposed forward of the lateral clamps. As shown, the ski boot 8 
is secured on the surface of the ski by lateral clamps 4, 4', the latter 
being subjected to the action of a spring (not shown) disposed in a casing 
105 secured forwardly of the toe of the boot 8. As before, the clamps 104, 
104' are carried by arms 146, 146' pivotally mounted on the ski (see FIGS. 
11 and 12), and are connected to a strip 145 by means of rods 148, 148'; 
149, 149', the strip 145 sliding longitudinally and coacting by its 
forward end with the elastic member (not shown) by means of a crank device 
which may be similar to the one described in connection with FIGS. 11 and 
12, the pivotal axle 138 of lever 106 being of course displaced so that 
the latter will be located in the lower position (see FIG. 18) when the 
binding is closed (operative position). 
In addition to the advantages already mentioned, namely simplicity of 
construction and operation, assurance of disengagement of the boot in case 
of a fall, improved durability thanks to the reduction of friction, the 
binding device according to the invention has moreover the advantage of 
being adapted easily to be combined with an automatic donning system for 
this binding. Thus, given that it suffices for changing from the open 
position of the clamps to their closed position by acting on the crank, it 
is possible therefore to provide means acting on this crank, or on the 
strip connected to it, adapted for example to be actuated by the 
positioning of the ski boot. Thus, this member may be combined with a 
braking or stopping device with which the ski is provided, for example as 
shown in FIGS. 11 and 12, or in any other manner not specifically 
described herein.