FIELD OF THE INVENTION

The present invention relates to a roller ski shock absorber system connectable to a shaft supporting roller ski wheels.

BACKGROUND OF THE INVENTION

Roller skis is a popular form of skis used on dry land in summertime and is used both for amateurs as well as competing athletes doing cross-country skiing. It is evident that the experience of using roller skis on dry land compared to using real skis on snow is a different experience. However, if you want to train and improve your skills on skis also in summer on dry land the roller skis may be used if they to some extent can emulate the feeling of running on snow. Roller skis are normally used on hard road surfaces which are reflected in the legs of a skier on the roller skis. This may be different from running on snow which normally are softer than asphalt for example. One example of an effect that is present when skiing on asphalt is vibrations which tends to make a skier running differently than what could be done on real snow. Fatigue of certain muscles may be present on asphalt and not on real snow. Therefore, vibrations may build wrong muscles and not enhance the ski technique on snow for the skier.

In prior art a shock absorber system arranged for example between respective wheels and a body of a roller ski is intended to mitigate some of the problems discussed above.

US 20080030014 Al disclose an apparatus supporting "dry land" simulation of the diagonal stride cross-country skiing technique. The apparatus may include a roller ski comprising at least two wheels configured to roll on a surface and a stop connected to the roller ski. The stop may selectively engage at least one of the surfaces and the at least two wheels in response to a force of at least a threshold magnitude urging the roller ski toward the surface to resist rearward roll of the roller ski on the surface. The resistance to rearward roll may vary with the force.

However, further problems with roller ski techniques emulating running on real snow may be related to running through turns. When a skier approaches a turn, for example when turning to the right, the inner side of the roller ski facing inwards to the center of the turn will be compressed towards the surface while the opposite side of the ski facing away from the center of the turn will be somewhat lifted. Therefore, a shock absorber system my need to tackle independently movements on both sides of a roller ski moving around a turn. Correspondingly, moving across an uneven surface may act on a shock absorber with different impact force related to which part of a roller ski wheel being affected while crossing a pit or an increase on the road surface.

RS 20120334 Al disclose a ski for asphalt (roller skis) with flexible ends. The wheel (6) axle is fixed to the brackets (4) of the wheel (6) axle which are mounted on the end of the spring (3) and it is allowed in the set limits to produce the flexible movement up and down whereat the shorter part of the spring (3) is permanently fixed in the rear part of the channel (2) of the ski fork (1). In the elimination of vibration, the spring (3) at lower ski loading and the rubber shock absorber (5) participate at the moment when the skier's body weight is completely transferred to the body of the ski (7).

US 2004100043 Al disclose a shock absorbing system for an in-line skate comprising a washer wherein the washer is composed of a rigid center for insertion of wheel axles surrounded by a resilient material to provide shock absorption especially while performing jumps and tricks. The washer can be incorporated into the skate at the time of manufacture or may be inserted as a post-market modification.

US 5975542 A disclose A wheel-supporting hanger for utilization on the frame of a roller skate, this hanger having an upper mounting portion as well as front and back portions. A central cavity is defined in the front portion of the hanger, in which an axle-receiving member is operatively mounted in a cantilever manner. A wheel-supporting axle protrudes outwardly in a cantilever manner from the axlereceiving member, with a screw utilized on the outer end of the axle for retaining a skate wheel in an operative manner on the axle. A structural member is located in an upper part of the cavity, defining a substantially flat undersurface in a relatively closely spaced relationship to the axle-receiving member. The cantileverly mounted axle-receiving member, because of the mounting of the axle therein, is permitted to flex upwardly as well as to move laterally to a controlled extent should the wheel mounted on the axle encounter an obstacle or obstruction. The axle-receiving member, in the instance of lateral movement, moves a commensurate distance with respect to the substantially flat undersurface, with this movement lessening the chance of material stress to the skate as a result of the shock of the skate wheel striking the obstacle. I prefer to utilize an insert of resilient, shock absorbing material between the axle-receiving member and the flat undersurface, with this insert being of selectable hardness so that the degree of permissible vertical travel of the axle can be closely controlled.

NO 20200078 disclose a roller ski shock absorber comprising a wheel carrier (1) and a shock absorber carrier (3) bound together by a rubber strip (2) during vulcanization of the rubber strip. The shock absorber carrier is attached to a roller ski end (4) of the body of the roller ski and the wheel carrier (1) is protruding out from the roller ski end (4) holding a wheel via an adapted wheel axel (6). The roller ski shock absorber is capable of rotating around a center of rotation (7) arranged at a distance from the backend of the roller ski being 2/3 of the rubber strip (2) length. The wheel carrier is extending outside the backend of the roller ski end (4) with a distance that is larger than the radius of the wheel thereby the wheel can spin without interfering with the roller ski (4).

This implies that the distance between the center of the wheel attached to the wheel carrier and the center of rotation is relatively long. Any forces acting on the wheel is therefore transferred to the center of rotation (7) providing a torque on the center of rotation (7) being the acting force multiplied with the relatively long distance.

Therefore, there is a need of an improved shock absorber system arrangeable in roller skis.

OBJECT OF THE INVENTION

It is an object of the present invention to provide an alternative to the prior art.

In particular, it may be seen as an object of the present invention to provide a shock absorber system being connectable directly to a shaft supporting a roller ski wheel. SUMMARY OF THE INVENTION

Thus, the above-described object and several other objects are intended to be obtained in a first aspect of the invention by providing a shock absorber system in direct contact with a shaft supporting a roller ski wheel.

The invention is particularly, but not exclusively, advantageous for obtaining a shock absorber system connectable to a shaft supporting a roller ski wheel comprising: a wheel support configured with at least one arm being insertable at least into a backend of a roller ski body, a circle shaped end section of the at least one arm of the wheel support comprising a centered position configured to support an end part of a shaft supporting a roller ski wheel, wherein a circular shaped rubber or rubber like material is arranged around the centered position supporting the end part of the shaft supporting the roller ski wheel.

Respective aspects of the present invention may each be combined with any of the other aspects. These and other aspects of the invention will be disclosed and elucidated with reference to the embodiments described herein.

DESCRIPTION OF THE FIGURES

Figure 1 illustrates an example of embodiment of the present invention.

Figure 2 illustrates further details of the example of embodiment illustrated in Figure 1.

Figure 3 illustrates further details of the example of embodiment illustrated in Figure 1.

Figure 4 illustrates further details of the example of embodiment illustrated in Figure 1.

Figure 5 illustrates further details of the example of embodiment illustrated in Figure 1. Figure 6 illustrates the example of embodiment disclosed in Figure 5 viewed from a different angle.

Figure 7 illustrates an example of a roller wheel according to the present invention.

DETAILED DESCRIPTION OF AN EMBODIMENT

Although the present invention is disclosed in connection with specific examples of embodiments, it should not be construed as being in any way limited to the presented examples. The accompanying claim set defines the scope of protection of the present invention. In the context of the claims, the terms "comprising" or "comprises" do not exclude other possible elements or steps. Further, the mentioning of references such as "a" or "an" etc. should not be construed as excluding a plurality. The use of reference signs in the claims with respect to elements indicated in the figures shall also not be construed as limiting the scope of the invention.

Furthermore, combining individual features mentioned in different claims may possibly be advantageously, and the mentioning of these features in different claims does not exclude a combination of features is not possible and advantageous.

A roller ski comprises wheels in each end of an elongated roller ski body. At least a backend wheel (opposite the end of the roller ski being pushed forward) may comprise different types of shock absorbers as known in prior art. Even though a shock absorber may be effective there is usually a metal contact between a shaft holding a roller ski wheel and for example an arm in contact with the shock absorber system. This may provide a transfer of vibrations from a road surface as discussed above.

Figure 1 disclose a sideview of a roller ski body 15. A wheel support 14 comprises an arm section inserted into the roller ski body 15 (not visible) and an end section 21 wherein a wheel 13 is attached to a center position 11 arranged on the end section 21 of the wheel support 14. There is an angle between respective arms of the wheel support 14 and the end section 21 lifting the center 11 of the end section 21 above a top surface of the roller ski body 15. The angle can also be arranged such that the center 11 of the end section 21 will be located below the top surface of the roller ski body 15. Thereby the height about the ground of a roller ski body 15 can be adjusted. It is also possible to arrange the wheel support such that a front part of a roller ski body 15 is inclined upwards or downwards relative to a back end of the roller ski body 15.

Around the center position 11 of the end section 21 there is arranged a section 10 of a rubber or a rubber like material. This part is arranged with a through hole that enables insertion of a screw or bolt 12 that can engage a shaft supporting a wheel body 13.

This arrangement provides a non-metallic connection between a shaft supporting a wheel and a wheel support 14. Further details are disclosed below.

The wheel support 14 comprises two members each extending to the center of a wheel on both sides of the wheel. One member is a mirrored version of the other. Screws or bolts 12 can then fasten a wheel to the wheel support 14 on both sides of the center of the wheel. Further details are provided below.

Figure 2 illustrates a shaft 16 configured to be located between respective members of the wheel support 14 illustrated in Figure 1. The illustration in Figure 2 is not made according measures of an actual embodiment of the shaft 16 but is provided to illustrate certain details of the present invention.

The shaft 16 is arranged with a ball bearing 17 located on a middle section of the shaft 16. A wheel 13 is configured to be placed on the ball bearing 17 as illustrated with the arrow 19.

One aspect of the present invention is that a rotating wheel is not turning the shaft 16 around. The ball bearing 17 supports the rotation.

The ball bearing 17 is a one-way rotating ball bearing. This ensures that a roller ski body 15 cannot roll backwards. Each respective ends of the shaft 16 is arranged with indents 18a, 18b configured with flat surfaces thereby forming a tap like protruding element. Each end of the respective tap like elements facing away from the shaft 16 is arranged with a threaded hole 20. The respective treaded holes 20 are configured to receive a bolt or screw 12 inserted from the outside of the wheel support 14 as discussed with reference to Figure 1.

Figure 3 illustrates further details of a wheel support 14 according to the present invention. The wheel support 14 comprises two members 14a, 14b that are connectable to each other with threaded bolts insertable into adapted threaded holes arranged in respective protruding elements 23, 24. An example of how an assembled wheel support 14 looks like is illustrated in Figure 5 and 7. The end surfaces of the respective protruding elements 23, 24 are adapted with a form of diamond shaped surfaces providing a strong mechanical connection between the respective members 14a, 14b of the wheel support 14.

The respective arms of the wheel support members 14a, 14b forms a rectangular shaped frame when assembled that is configured to be insertable into for example a backend of a roller ski body 15. Thereby the respective end sections 21a, 21b of the respective members 14a, 14b will protrude outside the end surface of the roller ski body 15.

With reference to Figure 2 the respective ends of the shaft 16 is arranged with a threaded hole 20 enabling insertion and attachment of the screw or bolt 12 illustrated in Figure 1, thereby enabling attachment of a respective roller ski wheel in between the members 14a, 14b at the respective end sections 21a, 21b.

With reference to Figure 2, each respective end section 21a, 21b of the members 14a, 14b of the wheel support 14 has an adapted centrally located hole 22a, 22b shaped to fit the indents 18a, 18b configured in the respective ends of the shaft 16.

Figure 4 illustrates an example of a member of the wheel support 14 according to the present invention, wherein the circular shaped part 10 of rubber or a rubber like material is removed from the end section 21. The removal is indicated by a stippled line 10. Behind the material 10 there is a circular shaped space.

Inside the circular shaped space there is arranged a first metal part 26 arranged in a zigzag pattern around the inside periphery of the circular shaped space. Attached to a shaft 16 there is a second metal part 28 shaped partly in a circular form. In a diagonal direction of the partly shaped circular shaped part 28 there are two opposite outwardly pointing extensions. Each extension fits inside configured openings in the zigzag pattern of the first metal part 26. Between an outwardly pointing extension of the second metal part 28 and the respective configured openings of the first metal part 26 there is a clearance 25 that is in the order of millimeters, for example between five to two millimeters. Other clearance dimensions are within the scope of the present invention.

The first and second metal parts 26, 28 is made for example of aluminum. When a rubber or rubber like material 10 is added inside the circle shaped space in the end section 21, the rubber or rubber like material is applied in liquid form. After curing of the liquid rubber or rubber like material the rubber or rubber like material will function as disclosed above.

The clearance 25 can be defined for example by a width of the respective outwardly pointing extensions of the second part 28. The second part 28 is attached firmly to a surface of the shaft 16 but can also be arranged to be exchangeable. Thereby, it is possible to adapt the clearance dimension 25 within some defined limits. The size and dimensions of the first zigzag shaped metal part 26 may also be adjusted to change a width of the clearance 25.

Different dimensions of the clearance 25 can be embodied in a set of different wheels 13, wherein changing the clearance 25 is done by changing a wheel 13 with a different configures clearance 25.

It is also possible to apply the rubber or rubber like material 10 such that a pattern corresponding to the shape of the second metal part 28 is left in the cured rubber or rubber like material 10. The purpose of the clearance 25 is as follows. The ball bearing is constrained to only rotate in a direction moving a roller ski body 15 forward i.e., in the direction a skier is running. Therefore, any movement backwards of the roller skis are stopped. The stopping action of movement will provide a force onto the ball bearing 17 which is then transferring the force from the stopping action to the shaft 16. Since the shaft is connected to the rubber or rubber like material 10 inside an end section 21a, 21b and the end of the shaft ends 18a and 18b has flat surfaces the force will turn the shaft 16 inside the rubber or rubber like material 10. The second part 28 defining the clearance 25 is attached to the shaft 16 and will therefore move backwards relative to a forward movement with the defined distance provided by the clearance 25. This happens also when the rubber or rubber like material is present.

When comparing this action with how it feels when a skier is running on real snow a ski may move a little backwards when a skier pushes the skies forward. The clearance 25 provides therefore a better function of the roller skis when emulating skiing on real snow. The solution emulates the actions happening when skiing on snow.

Figure 4 illustrates also that an arm of the wheel support 14 ha a surface 30 arranged with two through holes 29. When a wheel support 14 is inserted into a roller ski body 15, for example in a backend surface, the surface 30 will contact an inside surface of the roller ski body 15. The arranged through holes is used to attach the wheel support 14 to the roller ski body 14.

Figure 7 illustrates an example of a roller ski wheel according to the present invention. The illustration A of Figure 7 illustrates how a ball bearing 17 is attached to the shaft 16 such that a part of the shaft 16 is extending outside the center of the wheel 13 and can be inserted into one of the adapted openings 22a, 22b illustrated in Figure 3.

The illustration B of Figure 7 disclose how an indent 13a is running around the periphery of the wheel along a centered line. The side surfaces of the indent are inclined running towards a bottom of the indent. This construction makes the roller wheel 13 function as if it is arranged two wheels side by side. Therefore, this arrangement improves the independent behavior of a first side of the wheel in relation to a second side of the wheel.

The present invention provides several improvements of roller skis emulating cross country skiing on snow.

Locating a rubber or rubber like material in a center of a wheel support can take up any movements in any direction of a shaft supporting wheels of a roller ski body because there are no metallic contacts between a shaft and the body of a roller ski. Especially, any vibrations induced by uneven surfaces are mitigated by this arrangement. Vibrations are rarely present when skiing on real snow. Therefore, this arrangement will emulate skiing on snow in a better manner.

The quality of the rubber or rubber like material 10 inside a wheel support 14 according to the present invention can be varied. When the rubber or rubber like material 10 is compressed different rubber or rubber like compositions can expand again after the compression with different speed, i.e., different reaction time. By choosing a hardness of the rubber or rubber like material 10 the reaction time can be controlled.

When a roller ski according to the present invention is running through a turn, for example to the right, a right hand side of the rubber or rubber like material will be stretched in an upper section closer to the roller ski body while a bottom part of rubber or rubber like material will be compressed. By choosing a specific adapted quality of the rubber or rubber like material the skier will not feel uneven surfaces even when running through a turn.

When a skier kicks off the roller ski body is pressed downwards. This implies that the rubber or rubber like material 10 will be compressed. Then, due to an adapted response time of the rubber or rubber like material, the response of the rubber or rubber like material will help a skier pushing forward.

However, when kicking forward on real snow it is common that the skis make a movement backwards before the ski is contacting the snow properly. On real snow ski lubrication is used to improve the contact performance of the ski onto the snow. The possibility to adjust the gap 25 between the first and second metal parts 26, 28 makes it possible to emulate these conditions better with roller skis running on dry land.

Another area of applications of the present invention that may benefit from the effect of the present invention is for example electric as well as manual scooters. Feedback from a front wheel of a scooter up to the handlebars may when running on a road surface transfer vibrations and shock impulses from a pit or increase in the road surface. Embodiments of the present invention can therefore be used in scooters and similar vehicles providing the beneficial effects of the present invention providing a smoother ride for a user of such vehicles.

According to an example of embodiment of the present invention, a shock absorber system may be connectable to a shaft 16 supporting a roller ski wheel 13, comprising: a wheel support 14 configured with at least one arm being insertable into at least a backend of a roller ski body 15, a circle shaped end section 21 of the at least one arm of the wheel support 14 comprising a centered position 11 configured to support an end part 18a, 18b of a shaft 16 supporting a roller ski wheel 13, wherein a circular shaped rubber or rubber like material 10 is arranged around the centered position 11 supporting the end part (18a, 18b) of the shaft (16) supporting the roller ski wheel (13).

According to the example of embodiment disclosed above, the wheel support 14 may comprise two members 14a, 14b wherein one member is a mirrored version of the other member, wherein the shaft 16 is supported in between the two members 14a, 14b.

According to the example of embodiment disclosed above, wherein the shaft 16 may be configured with a ball bearing 17 constrained to rotate in one forward direction supporting the roller ski wheel 13.

According to the example of embodiment disclosed above, wherein the shaft 16 may be configured with respective indents in the respective ends 18a, 18b having at least one flat surface forming a tap like protruding element configured to be insertable into adapted holes 22a, 22b located at the centered position 11 of the end section 21 of the at least one arm.

According to the example of embodiment disclosed above, wherein the respective indents of the ends 18a, 18b of the shaft 16 may be configured with a threaded hole 20 in an end surface of the shaft 16 orthogonal to the at least one flat surface of the respective indents 18a, 18b.

According to the example of embodiment disclosed above, wherein a bolt or screw 12 is configured to fasten a wheel 13 to the shaft 16 when inserted into the threaded hole 20.

According to the example of embodiment disclosed above, wherein a circular shaped space in the end section 21 may comprise the rubber or rubber like material 10 and a first zigzag shaped metal part 26 running along the periphery of the circular shaped space, and second metal part 28 attachable to the shaft 16 is configured with two opposite outwardly pointing extensions adapted to fit inside adapted openings in the zigzag pattern of the first metal part 26.

According to the example of embodiment disclosed above, wherein a clearance opening 25 is configured between the outwardly extending extensions of the second metal part 28 and the zigzag shaped first metal part 26.

According to the example of embodiment disclosed above, wherein a width of the respective outwardly pointing extensions of the second metal part 28 is defined to provide a certain dimension of the clearance 25.

According to the example of embodiment disclosed above, wherein the second metal part 28 may be changeable, wherein respective metal part 28 is arranged with different widths of the outwardly pointing extensions of the second metal part 28.

According to the example of embodiment disclosed above, wherein the wheel 13 is configured with an indent 13a running around the periphery of the wheel 13 along a centered line, wherein side surfaces of the indent are inclined downwards towards a bottom surface of the indent 13a.