[0001] This invention relates to a counter-tip device for skis.
[0002] Competition or sporting skis frequently have the disadvantage of vibrating on account
of the stresses imposed thereon while in use.
[0003] That effect is most evident at the tip of the ski and may be particularly troublesome
for the skier in addition to being a sure cause for losing speed.
[0004] In addition, in sport events of the slalom type, where the skier is to complete a
distance between gates formed by poles, it may easily occur that the ski tip, when
brought too close to the pole, gets caught in it causing the skier to fall or at least
be disqualified on the ground of an irregular passage of the gate.
[0005] Of course vibration of the ski tips constituting a cause for difficult control of
the skis may constitute a cause of engagement with the poles present along the track.
[0006] It is an object of this invention to provide a device which has such characteristics
as to reduce the effects of vibration of the ski.
[0007] A further object is that of providing a device, which by virtue of the configuration
of the tip of the ski reduces the risk of engagement of the ski with the poles of
slalom gates, even when they are struck by the skier.
[0008] Another object is to provide a device which is readily attachable to a ski without
substantially altering its structure.
[0009] A not unimportant object of the invention is to provide a device which, when attached
to a ski, imparts particular properties of safety and manageability thereto, particularly
appreciable in competition type skis.
[0010] Still another object is to provide a device of simple operation and low cost.
[0011] These and other objects such as will be apparent hereinafter are achieved by a counter-tip
device for skis, characterized in that it comprises a generally flat body having a
seat formation for inserting therein a ski tip and vibration-dampening means on said
body.
[0012] The Applicant has conducted experiments involving the utilization of a guiding rod,
mounted substantially vertically in said chamber and including disks formed of a material
having a high specific weight mounted slideably thereon and guided thereby along the
rod. However, it has been found that such provision provides less attenuation of vibratory
movements of the ski tip than an incoherent mass. In fact this cited arrangement of
a rod and slideably mounted disks is only effective to attenuate some components of
vibration generated by forces acting, in the plane containing the axis of the rod
and at most, only a small portion of the forces acting in other intersecting planes,
while gravity forces and centrifugal and inertia forces cannot be coped with such
arrangement.
[0013] With this invention the gravity forces, the centrifugal forces and the inertia forces
or momentum are exploited so as to contribute to the vibration-dampening effect.
[0014] Further features and advantages of the invention will be apparent from the detailed
description of a preferred embodiment given by way of illustration and not of limitation
with reference to the accompanying drawings, where:
Figure 1 is a plan view of a pair of ski tips incorporating the device according to
the invention;
Figure 2 is a mid-sectional view of the tip of a ski incorporating the device aceording
to the invention embodied in a first form thereof;
Figure 3 is a sectional view taken on a center- plane of an equivalent device of that
shown in Figure 2 but implemented with a different configuration;
Figure 4 illustrates a modified construction of the device of this invention;
Figure 5 is an exploded mid-sectional view of the device shown in Figure 2; and
Figure 6 is a mid-sectional view of a ski, to which the device of Figures 1,2,3 and
5 may be fitted.
[0015] With reference to the cited figures, the device according to the invention, in a
first embodiment thereof, is shown in Figure 1 where it is mounted on the tips respectively
of a left ski 1 and right ski 2.
[0016] The device comprises a counter-tip respectively indicated at 3 and 4 for the left
ski and for the right ski, said counter-tip including a shaped body which partially
overlaps the ski tip, having in this area a seat respectively 5 and 6 for the two
skis 1,2, said seat 5, 6 being shaped to match the tip 1,2 of a ski which is to be
contained therein. The seat may be pocket-like, if desired.
[0017] This counter-tip is extended, in this embodiment, with an asymmetrical pattern curving
inwards to terminate with a pointed front zone respectively 7 and 8, so shaped as
to define, with the two skis 1 and 2 laid with their inner edges 11a, 11b side by
side, a shape substantially resembling a single ski tip.
[0018] In practice the counter-tip, making reference for example to the ski 1, is a continuation
of the outer edge 9 of the ski into a curved zone indicated at 10, and continues until
the pointed zone 7 is substantially aligned with the inner edge 11 of the ski.
[0019] According to another embodiment the counter-tip may be symmetrically arranged with
respect to the center line of the ski.
[0020] With reference now to the drawing figures 5 and 6, the containment and the fixing
of the tip of the ski 2 within the seat 6 will be described.
[0021] The pocket seat 6 formed in the counter-tip 4 is defined by an upper wall 4a adapted
to engage with the upper side 2a of a ski 2 and a lower wall 4b adapted to engage
with the lower side 2b of said ski 2. Said lower wall 4b being formed with first 301
and second 302 protuberances adapted to be received within first 300e and second 300b
correspondingly shaped through holes formed on the ski 2. Said protuberances 302 and
301 include centrally located through holes 300a, 300d, which are coaxial with through
holes 300b, 300e when in assembled condition and being adapted for allowing passage
therethrough of screws 21,14, respectively. Said upper wall 4a of said counter-tip
4 including a third protuberance 303 adapted to be received in the hole 300b, and
having a centrally located threaded dead hole 300a coaxial with the centrally located
through hole 300a of said lower wall and said through hole 300b of said ski 2 for
fixing engagement with said screw 21, when in assembled condition.
[0022] Said upper wall 4a further including a large through hole 313 adapted to accommodate
a boss 13 therein. Said boss 13 being formed with a projection 304 adapted to be received
within the hole 300e formed in said ski 2, and having a centrally located threaded
dead hole 300f coaxial with the centrally located through hole 300d of said lower
wall 4b and said through hole 300e of said ski 2 for fixing engagement with the screw
14, when in assembled condition.
[0023] Advantageously, the counter-tip 4 is formed of a material having inherent elastic
properties permitting said upper wall 4a and said lower wall 4b to be spread in the
direction of the arrows A, B in Figure 5, thus allowing for insertion of the tip of
a ski 2 therein.
[0024] The boss 13 may then be inserted into the large through hole 313, with its projection
304. Screws 14, 21 may then be inserted into the now aligned holes 300a, 300c and
300f, 300d wherein, appropriate tightening thereof will clamp and secure the entire
assembled structure causing the counter-tip 4 to become substantially integral with
the tip of the ski 2, as illustrated in Figure 2.
[0025] Shown in Figure 2 is a section of the right ski 2 where the boss 13 is brought out
with the through screw indicated here at 140
[0026] On each counter-tip 3 and 4 at a location corresponding to the tips of the skis 1
and 2 there is present a vibration-dampening unit indicated, in Figure 1, at 15 and
16.
[0027] As shown more clearly in Figure 2, the vibration-dampening unit 16 comprises an outwardly
substantially frusto-conical hollow body 17 rigid with the counter-tip which is in
this case indicated at 4 and having on its interior a substantially cylindrical cavity
or chamber indicated at 18.
[0028] Said hollow frusto-conical body 17 is closed by a cover 19 for example force fitted
whilst the bottom 20 of the vibration-dampening element is attached to the ski tip
2 by means of a screw 21, passing through the underside of said counter-tip 4 and
through said ski 2 tip into said bottom 20 of said vibration-dampening unit 16.
[0029] Said cylindrical cavity 18 contains an incoherent mass formed in this first embodiment
by a liquid 22 having a high specific weight which only partly fills the cavity 18.
[0030] Said liquid 22 may be conveniently oil or even a liquid metal such as mercury.
[0031] The operation of the device is readily apparent.
[0032] Vibration of the ski at the tip area thereof causes shaking and splashing of the
liquid 22, within the chamber 18, impacting against the bottom, cover, and sidewalls
of the chamber resulting in energy being dissipated, thereby causing the vibration
of the tip of the ski to be dampened.
[0033] The ski tip vibrations are generated by forces which may have vectorially different
and varying directions.
[0034] The presence of a liquid which can move randomly within the chamber 18 allows for
good opposition to any forces creating vibration of the tip.
[0035] Actual experimental tests have shown that the vibration is markedly attenuated and
its duration with time is considerably reduced.
[0036] Shown in Figure 3 is a first variation of the vibration-dampening device.
[0037] In this case there still is a frasto-conical body 117 rigid with the counter-tip
104 mounted on the ski by tightening a screw 121 and a cylindrical chamber 118 closed
by a cover indicated at 119 which may be conveniently formed from a transparent material.
[0038] Said cavity 118 now contains a granulated material indicated at 122 which may conveniently
be sand, a powdered material having a high specific weight or even at least one metal
ball.
[0039] Also in this case the operation of the device is analogous to that which has been
previously illustrated.
[0040] During the vibration movements of the ski tip the granulated material contained in
the chamber 118 is set into motion and strikes the walls of the chamber causing energy
to be dissipated and resulting in a reduction of the ski vibrations.
[0041] Figure 4 shows a further embodiment which comprises a cylindrical element 217 also
having on its interior a cylindrical chamber 218 fastened to the ski by means of a
screw 221 and closed at the top by a screw cap 219 which when threaded in or out adjusts
the free volume of the chamber 218 unoccupied by the mass 222, in a motionless condition
thereof.
[0042] Expediently, it is envisaged that the screw threads of the cited screw cap 219, communicate
with corresponding screw threads provided on the cylindrical element 217 in a tight
engagement relationship effective to prevent undesired unscrewing thereof. Alternatively,
means such as a "lock-nut" arrangement may be provided by locating a ring nut on a
lower portion of the screw threads of the cylindrical element, which by rotation thereof
may be moved towards the screw cap, until a secure abutment engagement is achieved
between the ring nut and the screw cap, thereby preventing their rotation and permitting
them to be "locked" at any desired location on the threaded part of the cylindrical
element.
[0043] The change of volume of the chamber 218 achieved by threading the screw cap 219 in
or out results in a change of the dampening effect due to shaking of the free mass
222.
[0044] All of the approaches set forth for the dampening device are substantially the equivalent
of one another and as already illustrated, their operating principle is based on the
presence of a free mass contained within a chamber, the volume hereof may advantageously
be adjustable, made rigid with the ski tip.
[0045] A further method of adjusting the dampening effect consists of securing the device
closer to or further away from the tip of the ski.
[0046] This may be accomplished by either providing a set of holes at the ski tip wherethrough
the fastening screws are passed, or a device may be provided with fastening adjustment
such as by means of engagement guides, etc..
[0047] The combination of a ski and a counter-tip preferably of an asymmetrical form and
hence with a suitable shape and a vibration-dampening device, imparts to the ski particular
properties of safety and manageability which are particularly appreciable in competition
type skis.
[0048] Of course, steps may be taken from the same inventive concept to assume different
practical embodiments of the invention, and any dimensions and materials may be selected
and used depending on individual requirements.
1. A counter-tip device for skis, characterized in that it comprises a generally flat
body (3,4) having a seat formation (5,6) for inserting therein a ski tip (1,2) and
vibration-dampening means (17,22, 122) on said body (3,4).
2. A device according to Claim 1, wherein said body has a shape corresponding to the
shape of the ski portion to be inserted therein.
3. A device according to Claim 1, wherein said body (3,4) has a shape deviating at
least in part from the shape of the ski portion (1,2) to be inserted therein.
4. A device according to Claims 1, 3, wherein a forward end portion of said body (3,4)
deviates sidewise with respect to a center line thereof corresponding to the center
line of the ski portion (1,2) to be inserted therein.
5. A device according to Claim 4, wherein the other side of said end portion opposite
to the side towards which the end portion deviates has a convex curvilinear shape
(9,10) and wherein said forward end portion terminates with a tip (7) offset sidewise
with respect to said center line of said body.
6. A device according to Claims 1-5, wherein said body has a hollow body portion (17)
containing in the interior thereof an incoherent free mass (22,122,222), which by
virtue of its inertia dampens the vibratory movement of the ski tip.
7. A device according to Claims 1-6, wherein said body (3,4,104) is fastened to the
ski tip (1,2) by mechanical means (12,13,14,21,121,221).
8. A device according to Claim 7, wherein fastening of said body (3,4,104) to the
ski tip (1,2) is accomplished by means of through screws (14,21,121, 221).
9. A device according to Claims 6-8, wherein said incoherent free mass (22,122,222)
comprises a heavy granulated element such as sand or at least one metal ball which
only partially occupies the hollow chamber (18,118,218) in said body (17,117,217).
10. A device according to Claims 6-8, wherein said incoherent free mass (22,122,222)
comprises a heavy liquid such as oil or heavy liquid metal such as mercury.
11. A device according to Claims 6-10, wherein said hollow body (218) comprises a
closure cap (219) threaded thereon for adjusting the volume of the cavity of the hollow
body, said cap (219) being optionally formed from a transparent material.