[0001] The present invention mainly concerns an arrangement in a ski binding for fastening
a skiing boot provided with a front sole extension which has a smaller width than
the remaining sole, comprising a toe iron with an approximately plane mounting plate
and a portion intended to support the sole extension, and a portion facing to the
rear and intended to support the front portion of the wider sole portion, and with
the front portion of said toe iron being provided with a means for holding the toe
extension, and with the portion of said mounting plate serving as a support of the
sole extension being provided with lateral portions that are bent up to serve as
lateral supports of the sole extension. The invention also relates to a skiing boot
intended for use in connection with said ski binding.
[0002] In ski bindings of the above kind only the sole extension facing forward is fastened
to the ski. Any bending of the boot sole, thus, occurs in the forward area of the
boot sole, in the last phase of kick off bending occurs quite in front, at or even
in front of the toe area of the foot. The object of such a binding is that the skier
should achieve maximum length of step in kicking off. Utilization of such bindings
is rendered possible by the very carefully prepared trails we find almost everywhere
to day.
[0003] Obviously, the ski boot receives hardly any lateral control by such a binding. This
has a negative effect in case of downhill running when a lateral force will act on
the boot when the skier turns, said force urging the boot out relative to the ski.
With the extremely light-weight boots used today this is a considerable disadvantage.
Also when the skier goes upphill and has to put the skis at a certain angle relative
to the trail direction (herring-bone) there will be lateral forces acting on the boot.
[0004] In order to remedy this disadvantage it is known to provide guide cam means both
at the sole and at the heel for cooperation with grooves in the boot sole or boot
heel. Such guide cam means with cooperating grooves were arranged in the central
portion of the boot and extend approximately in parallel with the longitudinal direction
of the ski.
[0005] When the new skiing technique with skating is used other forces will occur between
boot and ski. In kicking off, especially during the last phase of kicking off the
skier's foot will direct a force forming a certain angle with the vertical line on
the ski surface. This means that the skier tends to lift the outer side of the boot
from the ski, which is due to the fact that the ski is laterally inklined in connection
with skating. causing the contact between ski and snow support occurs essentially
on the lower half of the ski. Centrally provided guide means will, thus, not have
much effect, since the boot sole is mainly in contact with the lower edge of the ski.
[0006] Another disadvantage of the above mentioned bindings is that they have a very restricted
extension in the longitudinal direction and, thus, essentially only support the sole
extension and, possibly, the foremost portion of the wider sole portion.
[0007] With the extremely narrow skis used to day a skier having a relatively wide foot
will, thus, have insufficient support for the widest portion of the foot, i.e. ball
of the foot, which is the portion of the foot to receive most contact pressure against
the ski and, thus, the heaviest load. For skiers kicking off strongly when skating
the thin sole of a modern ski boot will bend in the longitudinal direction of the
sole, and this may cause a painful load. Some skiers had to reinforce the sole by
the aid of a material with high bending strength.
[0008] It is an object of the present invention to eliminate the above mentioned disadvantages
and to propose an arrangement in a ski binding of the kind mentioned above to achieve
good lateral guidance when skating steps are used and, furthermore, an improved support
of the wider portion of the skiing boot at the ball of the skiers foot. It is also
an object of the invention to propose a skiing boot for use in connection with such
a ski binding.
[0009] According to the invention this is achieved by the aid of a ski binding of the kind
mentioned above which is characterized by the fact that the portion of the mounting
plate that is intended for supporting the front portion of the wider part of the sole
has a smaller width than that of the cooperating sole, and that the edges of said
portion of the mounting plate are provided with bent up lateral edges with a smaller
height than the thickness of the sole and intended for cooperation with grooves in
the underside of the sole.
[0010] A preferred embodiment of the invention is characterized by the fact that each of
the two lateral edges of the mounting plate follows a straight line, so that the bent-up
lateral portions for supporting the edges of the sole extension form a straight extension
of the bent-up lateral portions at the portion of the mounting plate that is extended
rearwards. Further features of the binding will appear from dependent claims 3 and
4.
[0011] An arrangement in a skiing boot with a front sole extension which has a smaller width
than the remaining sole, for use in connection with a ski binding og the kind mentioned
above is characterized by the fact that the sole extension turns into a wider portion
of the sole via steps on both sides of the sole, and that a groove is provided in
the underside of the wider sole portion, starting from the inner corner of the steps/shoulders
and extending rearwards.
[0012] The invention will now be disclosed in more detail with reference to the drawings,
showing embodiments of the invention.
Figure 1 shows a binding according to the invention,
Figure 2 shows the underside of a boot sole according to the invention, and
Figure 3 shows a variant of the binding according to Figure 1.
[0013] Binding 1 in Figure 1 comprises a toe iron 1 with a plane mounting plate 2. Mounting
plate 2 is wider at its rear edge than at its front edge, and the lateral edges 3
and 4, thus diverge from the front to the rear. Each of the lateral edges 3 and 4
are provided with bent-up edge portions 5 and 6. The front portion 5′, and 6′, respectively,
of said edge portions is intended as a lateral guide for the sole extension 7 of sole
8 of a skiing boot. Said portions 5′, 6′ have the same or greater height than the
thickness of extension 7. The rear portions 9 and 10 of the bent-up lateral portions
5 and 6, respectively, have less height than the bent-up portions 5′ and 6′, respectively,
and they also have a smaller height h than thickness t of the boot sole (cf. Figure
3). Mounting plate 2 of toe iron 1 is provided with apertures for fastening the toe
iron to a ski 12. At the narrow front portion 2′ of the mounting plate which serves
to receive and support the sole extension 7 pins 13 projecting upwards are provided
to cooperate with and pass through corresponding apertures 14 in the sole extension
7 when in use. At the front portion 2′, furthermore, a fastening means for the boot
sole extension 7 is provided. Said fastening means is commonly known and, thus, does
not form part of the invention. In Figure 1 it is shown as a simple clamping means
comprising a threaded pin 15 which is fastened at the front portion 2′ of mounting
plate 2. A plate 16 with an aperture 17 is provided to be fitted onto pin 15 after
a skiing boot with its sole extension 7 is inserted into the toe iron, so that pins
13 engage in apertures 14. Sole extension 7 is clamped to plate portion 2′ by the
aid of plate 16 and a wing nut 18. In Figure 3 another embodiment of a fastening means
is shown. This latter means comprises an angular lever 19 which is rotatable about
an axle 20 which is firmly arranged in upwards extended lugs 21 of the lateral edges
5′. In the Figure the binding is shown in a position for use with the boot fastened
in the binding, and the locking arm 19′ of lever 19 turned to an over centre position
and clamping the boot sole. The pressure from the locking arm may, if desired, be
distributed by a pressure plate not shown. Actuating arm 19ʺ of lever 19 is pressed
down towards the upper side of ski 12 and forms a sloping face which will prevent
snow from collecting inside the binding.
[0014] As will appear from Figure 2 the wider portion of the sole turns into the front sole
extension 7 via steps 20, 21. From the corner 22, i.e. the transition between steps
20, 21, and the sole extension 7 grooves or channels 23, 24 are provided in the underside
of the sole to correspond to the cams or bentup lateral edges 9, 10 of the toe plate.
When the skiing boot is mounted grooves 23, 24 will, thus, engage the bent-up portions
9,10 and form an efficient lateral guide. The lateral guide will be efficient both
for diagonal gait, i.e. when the ski is moved flat on a ski track, and for skating
steps as well. Even if the boot is placed on edge, i.e. inclined relative to the surface
of the ski, the boot will be in engagement with the inner cam or the raised portion
9 og 10 will be in inside groove 23 or 24 all the time.
[0015] As will appear from Figure 2 the toe iron of the binding provides for good support
to the wider portion of the sole, since the toe iron supports most of the surface
of said wider portion all the way back to the ball of the foot. Thus, the sole is
prevented from sagging towards a narrow ski.
1. An arrangement in a ski binding for fastening a ski boot with a front sole extension
(7) which shows less width than the remaining sole (8), comprising a toe iron (1)
with an approximately plane mounting plate (2) having a portion (2′) which is intended
as a support of the sole extension, and a portion (2ʺ) directed rearwards and intended
as a support of the front portion of the wider part of the sole, and where the front
portion of the toe iron is provided with a means (15, 16, 17, 18) for firmly holding
the sole extension, and where the portion of the mounting plate serving as a support
of the sole extension is provided with bent-up lateral porttions (5,6) serving as
lateral supports for the sole extension, characterized in that the portion (2ʺ) of the mounting plate intended as a support of the front portion
of the wider part of the sole (8) has less width than the cooperating sole, and that
at the edge of said portion (2ʺ) of the mounting plate there are bent-up lateral edges
(9, 10) of less height than the thickness of the sole and intended for cooperation
with grooves (23, 24) in the underside of the sole.
2. An arrangement as defined in claim 1,
characterized in that each of the two lateral edges (3,4) of the mounting plate follows a straight
line, so that the bent-up lateral portions (5′,6′) for supporting the edges of the
sole extension form a straight extension of the bent-up lateral portions (9,10) of
the portion (2ʺ) of mounting plate (2) that is extended rearwards.
3. An arrangement as defined in claims 1 and 2,
characterized in that the two laterial edges (5,6) of the mounting plate diverge in a rearward direction.
4. An arrangement as defined in claim 1, 2 or 3, characterized in that the bent-up portions (9,10) on the rearward directed part (2ʺ) of the mounting
plate have an upwards decreasing cross section.
5. An arrangement in a skiing boot with a front sole extension for use in connection
with the ski binding as defined in claims 1-4, characterized in that the sole extension (7) changes into a wider portion (8) of the sole via steps
at both sides of the sole, and the in the underside of the wider sole portion grooves
are provided from the inner corner of the step og angular apex (22) and rearwards,
adapted to the bent-up portions (9,10) of the binding.