Field of the invention

The invention refers to roller skis, more specifically, roller skis for outside activities, preferably to be used by elderly people and those, who suffer from musculoskeletal disorders.

Background

Modern roller skis are usually provided with chassis on wheels placed on the front and rear wheel axles. There is a leg mount on the chassis between wheel axles. It is more difficult to keep the balance on the roller skis compared to normal skis because the rolling resistance of the roller skis on a flat surface is less than the rolling resistance of the skis on the snow, and the roller skier’s center of gravity is higher than the skier’s center of gravity. Moreover, most roller skis are not provided with brakes.

To make it convenient to go roller skiing using classic skiing method, i.e. making wide strides, pushing back, rather than to the side and back, as when riding a skate, their wheels are usually provided with a ratchet mechanism that prevents the wheel from rotating backward. In addition, roller ski fasteners are made similar to ski fasteners, that is, they secure the toe of the boot, while the heel remains free and can be lifted when pushing off. In this case, however, the foot rests only on the metatarsus and phalanges of the toes and turns out to be strongly curved in the metatarsophalangeal joints, which leads to an increased load on these joints, especially on the first metatarsophalangeal joint. Meanwhile, elderly people often have this joint i damaged by arthrosis or arthritis.

For these reasons, roller skis are mainly used for training and fitness by athletes and people in good physical shape, and, accordingly, are practically not used for outside activities by the elderly or those who suffer from musculoskeletal disorders.

There are roller skis with a chassis on wheels mounted on the front and rear wheel axles, and a platform mounted on the chassis with an attachment that provides fixation on the platform of the skier’s foot (see US patent No.5901981 dated 11.05.1999). Roller skis are provided with a hand brake, the handle thereof is connected with a cable with a brake shoe designed to brake the rear wheel axle.

As the whole foot of the skier is fastened on the platform, there is no bending of the foot and increased stress on the metatarsophalangeal joints. However, for the same reason, such roller skis are inconvenient to be used by the classic skiing course. Moreover, because of the long, loose handbrake cable, it is inconvenient to handle roller skis, and the need to hold the handbrake handle while skiing creates inconvenience when using roller skis. There are also roller skis provided with a chassis on wheels mounted on the front and rear wheel axles, and flexible platform with a leg fastening, cantilever mounted on the chassis; and fastening can be adapted to fix the skier’ s foot on the platform, and the platform is connected to a brake adapted to braking the rear wheel axle (see US patent No.6082768 dated 04.07.2000). The brake contains a linkage connected with both the platform and the skier’s ankle. To brake, it is suffice to extend one leg forward so that the ankle of that leg tilts back and applies the brake, as shown in fig.5 US patent No.6082768.

Due to the flexible platform, the skier can lift the heel with the platform, moving it away from the chassis when skiing. Thus, there is no bending of the foot and increased stress on the metatarsophalangeal joints. However, due to the large variable loads acting on the flexible platform, there is a possibility of fatigue wear of the platform material, which can lead to its failure. Further, when attaching roller skis on the skier’s leg, a brake lever mechanism should be provided on the ankle, which is inconvenient. In addition, as can be seen from the above drawing (fig.5), one can brake with only one foot, which creates difficulties in terms of keeping one’s balance while braking. It can be difficult to maintain balance even when the skier is simply standing on the roller skis without moving or rolling forward downhill. For example, if such a skier loses balance and sways forward, the platform will begin to bend, and the skier, without any support, will keep falling. The platform may break with further falling and the skier may be bumped and injured. If a skier who is standing motionless or rolling forward loses his/her balance and sways backward, the roller skis can move or continue forward, and the skier, not finding support, will keep falling, because the brake will not work immediately, but only when the skier’s ankle is tilted back. But by this point, the skier may completely lose balance and fall.

The object of the invention is to create roller skis that enable the skier moving in a classic ski run, and at the same time having increased stability, and, accordingly, reduced injury risk. In addition, the object of the invention is to create roller skis, using thereof would prevent any bending of the foot and increased stress on the metatarsophalangeal joints.

Disclosure of the invention

The object of the invention has been solved due to the fact that in roller skis each provided with chassis on wheels mounted on the front and rear wheel axles, and a platform mounted on the chassis, which is equipped with a leg fastening made with the possibility of fixing the entire skier’s foot on this platform, and connected with a brake made to enable braking the rear wheel axle, the platform itself is mounted with the possibility of swinging forward and backward on a hinge located between the wheel axles. In this context, the term “swing forward” means a swing with front of the platform moving down and rear of the platform being lifted up. Accordingly, the term “swing back” means a swing with front of the platform being lifted up and rear of the platform moving down.

Due to the fact that the platform is mounted on a hinge with the possibility of swinging forward and backward, roller skis can be moved in a classic skiing course, i.e. roll forward in long strides. So, when making a step, the foot of the backward pushing leg is tilted forward on the hinge. Thus, the rotation of the foot required for walking is performed at the hinge, rather than at the metatarsophalangeal joint, preventing bending of the foot and increased stress on the metatarsophalangeal joints.

In the roller skis of the invention, the brake serves to stop while riding, and keep the balance. For example, if a motionless skier loses balance and sways backward, the platform pivots backward and the brake is applied, so the roller skis cannot go forward. If the skier loses balance and sways backward while skiing, the applied brake will create an inertial force forward and restore the skier’s balance. Thus, the skier will be supported and will be prevented from falling backwards.

If the skier loses balance and swings forward, the platform pivots forward and rests against the chassis surface, providing support for the skier’s toe, while a rigid heel will allow restoring the balance.

In modem roller skis, one wheel is usually installed on the front and rear axles. With the roller skis of the invention, the chassis can be mounted on four wheels like a bogie for added stability. In other words, there can be two wheels on the rear wheel axle, and two wheels on the front wheel axle. However, other combinations are possible, as if obvious to a person skilled in the art, for example, on the front wheel axle there can be one wheel, and two on the rear, or vice versa.

The platform can be provided with damping means, for example, spring-loaded ones. For this, for example, one spring can be installed on the chassis under the front part of the platform, and another spring under the rear part of it. However, other options for damping the platform are possible, as is obvious to a person skilled in the art. For example, hydraulic shock absorbers rather than springs may be installed under the front and rear of the platform. Or the spring can be integrated into the hinge. Damping means serve for a softer swing, as well as in order to create a force when the platform is tilted, returning it to a horizontal position.

For more effective repulsion, at least one of the wheels may include a ratchet mechanism to prevent the wheel from rotating backward.

Similarly to normal skis, roller skis can be equipped with hand poles for pushing off. With the roller skis being of the invention, the wheels can protrude laterally from the chassis. To prevent roller skis from snagging each other in motion, roller skis may be produced with wheels recessed into the chassis, as is obvious to a person skilled in the art. In both cases, the wheels can be covered with a smooth guard, which prevents the wheels of the roller skis from contact or snagging with each other.

Brief description of the drawings

Further, the invention is described by an example of its implementation with a reference to the drawings, where:

Fig.l is a schematic side view of the roller skis of the invention.

Fig. 2 is a schematic top view of the roller skis of the invention.

Fig.3 is a schematic front view of the roller skis of the invention (springs 14 and 15 are not shown for clarity).

Fig.4 is a schematic side view of the braking roller skis of the invention.

Fig.5 is a schematic view of the roller skis of the invention with smooth railings 17 running along the perimeter.

Implementation of the invention

Fig.1-3 is a schematic side view of one roller skis of a pair of roller skis. The ski roller is comprised of chassis 1 formed by metal plate 2 mounted on wheels like a bogie. More specifically, front wheel axle 3 and rear wheel axle 4 are attached to chassis plate 2. Axle 3 is provided with two front wheels 5, and axle 4 is provided with two rear wheels 6. As is obvious to a person skilled in the art, that the chassis can have no metal plate. For example, roller skis can be designed with chassis is made using a metal profile, for example, a channel, etc. Chassis can be also made from non-metallic materials that provide low weight and high strength, such as, for example, carbon fiber reinforced plastics.

Hinge 7 is provided between wheel axles, in the middle part of plate 2, where platform 8 is installed, equipped with a leg fastening, which is not shown in the drawings for clarity. The mount ensures fastening on the platform 8 of the skier’s foot. As is obvious to a person skilled in the art, such a fixation can be ensured by an attachment similar to that used on alpine skiing, or, for example, by the attachment presented in the aforementioned US patent No5901981. The platform 8, similarly to the chassis, can be provided with metal plate or can be made using a metal profile or can be made of non-metallic materials that provide low weight and high strength, such as CFRP. More specifically, hinge 7 comprises a lower lug 9, which is fixed to and protrudes upward from the chassis and its hole 10 extends laterally. A pivot pin 11 is inserted into the hole 10 of the eyelet 9, which is also inserted into the hole of the transversely narrower upper eyelet 12, attached from below to the platform 8, so that the platform 8 could swing back and forth. To accommodate the upper lug, a recess 13 is made in the lower lug (Fig.3).

In this example, the platform 8 is provided with damping means, namely spring-loaded ones. For this, a front spring 14 is installed on the chassis under the front part of the platform 8, and rear spring 15 is installed under its rear part. The forces of the springs 14, 15 are balanced, so that the platform 8 is initially in a horizontal position or, in other words, runs parallel to the chassis plate 2. Other options for damping the platform 8 are also possible, as is obvious to a person skilled in the art and therefore not shown in the drawings. For example, hydraulic shock absorbers rather than springs may be installed under the front and rear of the platform. A single spring can be also integrated into the joint to damp the swing both forward and backward. Damping means serve for a softer swing, as well as in order to create a force when the platform is tilted, returning it to its original horizontal position.

In the proposed embodiment of the invention, either rear wheel 6 is provided with a ratchet mechanism, which prevents rotation of this wheel backward. The ratchet mechanism, which is well known per se, is not the subject matter of the present invention and is not shown in the drawings; it is integrated into the wheel hub. The ratchet mechanism is used for more effective push-off when moving the classic skiing course.

The platform 8 is connected with a brake adapted to braking the rear wheel axle. More specifically, at the rear of the platform 8, on its lateral sides, brake rods 16 are disposed, each thereof projects laterally from the platform 8 and is mounted to engage with the rear wheel 6 when the platform is rocked backward, as shown in fig.4. As is obvious to a person skilled in the art, the brake can have no brake rods. For braking, one can use braking elements of a different shape, as well as any known braking mechanism, which is activated when the platform is swinging back.

As shown in fig.5, the wheels 5, 6 are covered with a smooth fencing 17 that runs along the perimeter of the roller skis and prevents the roller skis from snagging each other while riding. Fig.5 shows platform 8 and hinge 7 located below it and springs 14 and 15 are not shown for clarity. In the rest of drawings, fencing 17 is not shown for clarity.

When using roller skis, the skier moves with the classic skiing course, i.e. rolls forward, making steps. When making a step, the skier tilts the foot of the backward pushing leg on the hinge 7 forward. Thus, the foot rotation required for walking is performed on the hinge 7, rather than on the metatarsophalangeal, preventing foot bending and increased stress on the metatarsophalangeal joints.

To stop in motion, the skier shall shift his/her weight back; while the platform 8 swings back, and the brake rods 16 engages with rear wheel 6, which leads to braking. Similarly, braking occurs if a skier who is standing motionless or rolling down a slope forward loses his/her balance and sways backward. If the skier loses balance and sways forward, platform 8 pivots forward and rests against the surface of chassis 1, creating support for the skier, while a rigidly fixed heel will allow restoring balance.

Thus, the roller skis of the invention enable the skier moving using a classic skiing course, preventing bending of the foot and increased stress on the metatarsophalangeal joints, and ensuring increased stability, what makes their use by the elderly or those who suffer from musculoskeletal disorders possible.

Designations used on the drawings

1: Chassis 2: Chassis plate 3: Front wheel axle 4: Rear wheel axle 5: Front wheels 6: Rear wheels 7: Hinge 8: Platform 9: Bottom lug

10: Hole of the lower eyelet

11 : Hinge axle

12: Top lug

13: Upper lug notch

14: Front spring

15: Rear spring

16: Brake rods

17: Fencing