WO1986004556A1

WO1986004556A1 - Sledding disk

Info

Publication number: WO1986004556A1
Application number: PCT/FI1986/000010
Authority: WO
Inventors: Kari Mustonen
Original assignee: Plasto Olof Geelnard & Co., Kommanditbolag
Priority date: 1985-02-12
Filing date: 1986-01-27
Publication date: 1986-08-14
Also published as: FI850575L; FI71906B; FI71906C; FI850575A0

Abstract

The sledding disk (1) is formed by a cup-like seat portion (5) following the shape of the body of the rider, the forward portion (4) of which seat portion is provided with a handle (3) and the backward portion thereof with a braking piece (11) for slowing down the sliding when the sledding disk (1) is intentionally tilted backwards and the friction surface (11a) of the braking piece (11) is brought into contact with the sliding surface (12). In order to provide the best possible braking effect for a sliding surface (12) in each particular case, the braking piece (11) is replaceably attached to the seat portion (5) so that the rider can select the most effective friction surface (11a) in each case.

Description

Sledding disk

The invention relates to a sledding disk, e.g. a means for sliding downhill on ice or snow in a sitting position.

Today it is a fairly popular pastime of children and young people in particular to slide down a hill on various kinds of plastic toboggans and different kinds of planar sliding boards. It was the plastic trough-like toboggans that were first introduced into the market, in which especially younger children can position themselves in such a manner that their body is entirely within the sides of the trough which is of importance from the point of view of safety, because such sliding means cannot usual- ly be steered nor have they any braking means. Some models have been provided with braking means rubbing against the sliding surface, such braking means being formed by a claw-like projection which is pressed against the sliding surface by hand or by foot when braking. It has proved to be difficult to provide such braking means in this kind of plastic sliding means as a sufficiently firm structure and they are not generally used.

A braking means solution intended to increase the safety of the sliding means is represented by a braking list disclosed in German Patent Application 2,532,034, which list is positioned at the rear of the sliding means and which is made to rub against the sliding surface by tilting the sliding means backwards by shifting the center of gravity of the rider. The steering of the same means is also effected by tilting thereof, though now only side- wardly, whereby the guide lists provided on the bottom come into contact with the sliding surface, providing a steering effect in the direction of the tilting. In this model, too, the rider is entirely positioned within the sides of the device and cannot steer the sliding by means of his feet. The inside of said means is provided with a cushioning, which for its part protects the rider against shocks and, on the other hand, acts as a heat insulant against cold.

Braking means based on a backward tilting of the sliding means are disclosed also in German Patent Speci¬ fication 2,528,842 and U.S. Patent Specifications 4,320,905 and 3,782,7-44. Some of these devices can also be steered by tilting diagonally backwards.

A common disadvantage of the braking means disclosed in the above publications is that they always offer one and the same friction surface to be used for braking irrespective of the surface on which the means slide. In practice, the properties of the sliding surface vary within wide limits from a soft snow to a totally hard icy surface. A single braking list or other such friction sur¬ face stationarily attached to the sliding^'means already at the proudction stage cannot provide a satisfactory braking effect on a soft and a hard sliding surface.

In addition, said braking lists and the like wear down in use especially in connection with a hard sliding surface, thus losing efficiency thereof, and the replace¬ ment thereof has not been taken into account when planning said structures.

One aspect of these known devices decreasing the efficiency of the braking means is that they are so stiff and unresilient in construction that the friction surface cannot sufficiently adjust itself to an uneven sliding surface, whereby the actual braking area of the friction surface remains too small. This disadvantage is particu¬ larly obvious with hard sliding surfaces.

The stiff construction of known braking means is disadvantageous also in that especially on a hard sliding surface the shocks and bumps caused by an uneven surface are transmitted to the back of the seat in a braking situation without any dampening thereof and further to the lower part of the body of the rider thus, causing pain and even injuries.

Planar sliding boards are not at all provided with braking means, even though such means would be particular¬ ly necessary with this type of sliding means. This is due to the fact that the body of the rider is totally unpro- tected when such sliding boards are used, which results in numerous injuries when the riders bump into obstacles or each other. Legs are particularly liable to injury, because they are stretched out forwards on account of the planar seat portion of the sliding board. In a bumping situation, high strains are exerted not only on the legs but also on the hip and the lower part of the back. A great risk is involved 'in a brakeless sliding board if it is used too near a roadway as such mean^'s cannot be slowed down in time, and, besides, the steerability thereof is almost non-existent, wherefore it cannot be steered away from the direction of the roadway.

Trough-like and planar sliding means have been discussed above mainly as childrens' plaything, whereby safety is of crucial importance. However, young people have in recent times got more and more interested in sliding down steep and long slopes in a sporty way com¬ peting in speed and/or skill in deviating. This sport includes e.g. sliding down a winding course and over a bumpy surface. The traditional trough-like and planar sliding means described above are not expecially suitable for such a sport and it can be taken for granted in the assesment of safety that the riders, as compared with small children, are considerably more capable of control¬ ling their sliding means e.g. by steering means or by braking with legs. A trough-like sliding means has a poor steerability on account of the long bottom thereof and partly because it prevents legs from being stretched out properly for steering and braking. A sledding disk, in turn, is too difficult to be steered as it has little if any directional stability because of the planar shape thereof and, further, because the contact surface thereof can take any direction with respect to the underlying surface with equal ease. In short," the trough-like sliding means if too massive and the planar one oversimplified for sliding in a sporty way.

The sledding disk according to the invention pro¬ vides a decisive improvement in the above disadvantages. For the achievement thereof, the sledding disk according to the invention is characterized by the disclosure of the characterizing portion of claim 1.

The most significant advantage of the invention is that the speed of the sledding disk can be braked, if necessary, by means of a braking surface provided thereon, which surface can be easily replaced to suit the sliding ground in each particular case. Furthermore, the sledding disk is so shaped that the rider can control the sliding essentially better than with the previously known sledding disk as legs can be stretched out sufficiently for steering and maintaining balance. On the other hand, the shape- of the sledding disk ensures that the rider has to bend his knees, which increases safety, and, further, it supports the rider properly in every direction. A remarkable operational improvement of the braking means is achieved by providing a resilient material between the friction surface and the seat portion, ^"which material allows the friction surface to be adjusted to an uneven sliding sur¬ face, thus increasing the effective contact surface and, consequently, the efficiency of braking. The resilient material also lessens the effect of the bumps and shocks transmitted to the rider from an uneven surface. The shaping of the bottom of the sledding disk provides a better steerability and, accordingly, an increased safety as well as offers novel possibilities for adult riders taking interest in sliding down a winding course or over a bumpy surface in a sporty way.

The invention will be described in detail in the following with reference to the attached drawings. Figure 1 is a side view of a sledding means with a rider according to the invention,

Figure 2 is back view of the same sledding disk as a partial section along the line I-I of Figure 3,

Figure 3 is a top view of the same sledding disk, Fgiure 4 is a sectional side view along the line

I-I in Figure 3 of one way of fastening a replaceable braking piece and a resilient element thereof in accor¬ dance with the invention,

Figure 5 is a detailed view of a locking device used in the fastening of the braking piece according to Figure 4.

In Figure 1 , the sledding disk and the rider 2 sitting thereon are shown in a normal sliding position. The rider 2 holds a handle 3 of the sledding disk with legs stretched out beyond a forward edge 4 of said disk 1. The body portion of the disk is formed by a seat por¬ tion 5 of a two-layer structure, which seat portion follows the shape of the body of the rider 2 and the side walls of which are curved upwards on all sides. The in- side of said seat portion 5 is lined with a resilient heat insulating material 6, such as e.g. urethane, in which a seat 6a with thigh supports 7 and edge cushionings 8 there¬ of can be formed easily. Said resilient material 6 is at the manufacturing stage stationarily attached to an outer cover 9 of a sufficient stiffness and having a surface of sufficient smoothness, said outer cover forming the body of the seat portion 5 as well as the outer surface thereof. Further, the outer cover is provided with runners 10 stationarily attached thereto so as to improve the direc¬ tional stability thereof. The back portion of the outer cover 9 is provided with a replaceable braking piece 11 made of a resilient material and provided with a roughened friction surface 11a, which braking piece is brought into contact with a sliding surface 12 by shifting backwards the center of gravity of the rider 2 by tilting backwards the upper part of his body. The sledding disk 1 is thereby correspondingly tilted backwards, whereby the braking piece 11 begins to lean on the sliding surface 12, thus slowing down the speed by means of said roughened friction surface 11a the more effectively the more forcefully the rider 2 leans backwards. The braking piece 11 preferably extends over the whole width of the sledding disk 1 and is high as the backward wall of the outer cover 9 so as to provide a braking surface as large as. possible. The shocks and bumps caused by the irregularities of the sliding surface 12 can be eliminated to a certain extent by means of the resilience of the braking piece 11. In bumping situations, the resilient braking piece 11 acts as a buffer on the side of the back when the rider is sitting in the normal sliding position, whereby security is in¬ creased. A downwardly broadening ans stiffening arm 3a of the handle 3 as well as a forward edge 4 of the seat por¬ tion 5 protect the lower part of the body of the rider in bumping situations. In addition, the resilient material

11d between the friction surface 11a of the braking piece 11 and the outer cover 9 allows the friction surface 11a to adjust itself to the irregularities of the sliding surface 12, whereby the friction surface 11a is brought into contact with the sliding surface 12 as extensively as possible and an optimum braking effect is attained. The ability of the friction surface 11a to adjust itself to the irregularities of the sliding surface 12 is the more important the harder the said sliding surface 12 is. As appears from Figures 4 and 5, the braking piece

I 1 is replaceably attached to the outer cover 9 of the seat portion 5 in such a manner that projection latches 11b and 11c extending from the braking piece 11 are passed into counter notches 13b and 13c provided in the outer cover 9 of the seat portion 5, thus locking the braking piece 11 in place after it has been properly positioned and the resilient material 11d thereof compressed in such a manner that a notable prestress remaines in the latch means, preventing them from opening even during foreceful braking. The forces created during the braking are trans¬ mitted from the braking piece 11 to the outer cover 9 of the seat portion 5 and further to the entire sliding means through a pair of interlocking saw teeth 14a and ^• 14b, one half thereof being formed by a toothing 14a provided on the braking piece 11 and the other corres¬ pondingly by a toothing 14b on the outer cover 9 of the seat portion 5. The prestress provided by the resilient material ensures that said toothings remain interlocked. Tne resilient material of the braking piece 11 also pre¬ vents snow and ice from getting between the braking piece

II and the outer cover 9.

In the above embodiment, the braking piece 11 is intended to be resilient and to be attached to a moulded outer cover 9 as a separate body. If the braking piece is made non-resilient, it is of advantage for the ease of manufacture if the braking piece 11 is made of a suitably roughened plastic or metal plate provided with a scale - pattern, for instance, which plate is replaceably attached to the backward portion of the outer cover 9 of the seat portion 5. The fastening of a braking piece 11 which is not provided with a resilient material can be effected either by means of the latch means described above or by providing the backward portion of the outer cover 9 of the seat portion 5 with groove-like guides (not shown), the ends of the braking piece 11 being guided therein, whereby the vertical locking can be effected e.g. by means of quick-acting cotters (not shown) which are passed through the upper portion of the braking piece 11 and the outer cover 9.

Regardless of whether the braking piece 11 is provided with the resilient material 11d or not, it is essential to select a braking piece 11 provided with a friction surface 11a which in the best possible way suits the sliding surface 12 in question - a metal friction surface 11a having a finer pattern for a hard surface and a metal or plastic friction surface 11a having a coarser pattern for soft snow. The friction surface 11a of the braking piece 11 can also be double-acting in such a manner that the lower portion thereof has a finer pattern suited for an icy surface, the upper portion having a coarser pattern suited for a soft sliding surface 12. This embodiment has the advantage that one does not need to take along any sepa¬ rate braking pieces 11 when sliding under varying condi¬ tions. On the other hand, the braking effect attained is not as good as that attained when using separate friction surfaces 11a for an icy and a snowy surface. The runners 10 intended for improving the direc¬ tional stability can be replaced with a bottom having the shape of a broad V, whereby it is advantageous to form the forward portion of the bottom into a spherical surface which gradually turns into a V-bottom towards the backward portion. By virtue of a bottom shaped like this, the steerability of the sledding disk is essentially improved by tilting the body in the sideward direction.

The steerability along a winding couse in particu- lar can be improved by altering the shape of the bottom of the basic model described above by means of an addi¬ tional ski (not shown) which is separately fixed in the middle of the bottom (e.g. by means of screws), on which ski the sledding disk 1 slides. If a corresponding but less expensive product is to be obtained, it is naturally possible to leave out the two-layer structure with the inner linings, edge cushions and thigh supports thereof.

It is also otherwise to be noted that the invention has been described above only with reference to one pre¬ ferred embodiment thereof. The intention, however, has ^"by no means been to restrict the invention to concern this specific embodiment only, but modifications are possible within the inventive- idea defined in the follo- wing claims.

Claims

10Claims:

1. A sledding disk comprising a cup-like seat por- cion (5) preferably following the shape of the body and

5 a handle (3) attached to a forward portion (4) of said seat portion, and, further a braking piece (11) attached to the backward portion of an outer cover (9) of the seat portion (5) so as to slow down the sliding, said braking piece being brought into contact with a sliding surface

10 (12) by tilting backwards said sliding means, c h a r a c¬ t e r i z e d in that said braking piece (11) is replace¬ ably attached to the seat portion (5).

2. A sledding disk according to claim 1, c h a r ¬ a c t e r i z e d in that said replaceable braking piece

15 (11) is formed by a resilient material (lid) and a stiffer friction surface (11a) stationarily attached thereto.

3. A sledding disk according to claim 2, c h a r ¬ a c t e r i z e d in that the resilient material (11d) of the braking piece (11) has a hollow structure, the

20 cavities being connected with the ambient air through air passages in order to enchance the buffer effect.

4. A sledding disk according to claim 2, c h a r ¬ a c t e r i z e d in that said friction surface (11a) is replaceably and directly fastened on the backward portion

25 of the outer cover (9) of the seat portion (5) without any resilient material (11d).

5. A sledding disk according to claim 1, c h a r ¬ a c t e r i z e d in that said braking piece (11) extends over the whole width and height of the backward portion

30 of the outer cover (9) of the seat portion (5).

6. A sledding disk according to claim 2, c h a r ¬ a c t e r i z e d in that said friction surface (11a) is made of a wear resistant metal which is made skid-proof by embossing.

7. A sledding disk according to claim 2, c h a r ¬ a c t e r i z e d in that said friction surface (11a) is of a plastic material the surface of which is roughened.

8. A sledding disk according to claim 2, 6 or 7, c h a r a c t e r i z e d in that said friction surface

(11a) comprises two portions,the lower portion having a finer pattern suited for a hard sliding surface (12) and the upper portion a coarser pattern suited for a soft sliding surface (_.12).

9. A sledding disk according to claim 2, c h a r ¬ a c t e r i z e d in that said braking piece (11) is attached to the outer cover (9) of the seat portion (5) by means of a pair of saw teeth (14a, 14b) and pairs of latch means (11b, 13b; 11c, 13c).

10. A sledding disk according to claim 1, c h a r ¬ a c t e r i z e d in that the lower surface of the outer cover (9) of the seat portion (5) is provided with runners (10).