Device at roller skates The present invention is related to roller skates of the kind were the wheels are arranged in a row after each other, so called inlines. Inlines skates has traditionally four or five wheels to achieve easy rolling, sufficient support despite small wheels as well as to enable steering in a way similar to that of real skates on ice. In comparison to skating on ice however the skating with inlines is not as comfortable. The skating with inlines can quickly be exhausting for feet and ankles due to among any other things the vibrations that arise when the ground is not entirely even. The result is that one is not able to go as far as one believes and risk of wear damage to the feat may exist.

In view of the above the object of the invention is to achieve more comfortable roller skates of the inlines type that result in less strain and wear on the users foot and leg. In accordance with the invention this is achieved by the arranging of only two wheels, one in front of and one behind the shoe (foot) or in the front edge and the rear edge of this respectively. These wheels that are arranged in line with each other are each arranged in the outer end of a leaf spring extending inward under the shoe part itself of the inlines or the foot, where the leaf spring is fastened. In the outer ends the leaf springs are extended to forks surrounding and supporting the wheels. Due to the resilient arrangement via the leaf springs the wheels can move independently of each other and spring relative the ground and swallow the unevenness of this. Surprisingly enough it has turned out that it is sufficient with only these two wheels for skating on normal surfaces. Should so be wished the material in the wheels can be made somewhat harder than what otherwise is the case since the springs can compensate the lack of springing in the wheels in this case. What may also be surprising is that inlines in accordance with the invention despite the comparatively long distance between the two wheels can turn. Probably this is due to the flexible support of the wheels. The flexibility does not only prevent the vertical movements from being transferred to the foot of the user but also dampens lateral turning and swing movements.

By making the location of the wheels forwards and backwards in relation to the foot variable the inlines may be adjusted for short and swift skating respectively the skating over longer distances. At a calm skating a position is chosen with the wheels displaced rearward while at fast and long skating the wheels are placed more forward in relation to the foot.

Advantageously the two wheels are supported in a common leaf spring, which as unit

is displaceable lengthwise in relation to the foot and possible to lock in different positions.

Advantageously the leaf spring may be made of carbon fiber reinforced composite, which makes it light as well as resistent to outer influence of for instance salt. Also a U-shaped profile that grips over the leave spring can be made of carbon fiber.

In accordance with a further development of the inlines in accordance with the invention the comfort and the useability can be increased considerably by not only making the leaf spring adjustable below the shoe but also removable, which may be achieved with the same fitting as for the locking. By quite simply remove the leaf spring with the two wheels in this the inlines are transferred into a pair of shoes or skiboots with which for instance it is possible to enter the shops, walk at the side of the road etcetera. As is realized this improves not only comfort but also increase safety since one do not have to walk on the rollers of the inlines where this is entirely improper or perhaps even prohibited, stairs etcetera.

The unit constituted by leaf spring, forks and wheels may be made in different lengths and spring strengths that can be used independently of the shoe size. In addition to placing the leaf spring more to the front or to the back in relation to the foot adaption can be achieved by different mounting holes in the forks for the wheels. With long fork legs also wheels with greater radius can be used, for instance when skating on grass or small gravel.

Since the inlines in accordance with the invention lack wheels directly under the foot they may be provided with considerably larger wheels than usual inlines.

If so is desired the spring characteristic can also in a simple way be influenced for the front end and rear end respectively of the leaf spring by the arrangement of wedges or stops, for instance of rubber between leaf spring and shoe. By forming leaf spring and the receiving space on the bottom of the shoe respectively adapted to each other it is possible to achieve the effect of a strongly progressive springing, that is first comparatively soft then when the depression has become sufficiently large becoming harder since the leaf spring with an increased part is in contact with the bottom of the shoe and only springs with a small free part.

The leaf spring can preferably be rectangular to its cross section. One can even consider other shapes if for instance an increased lateral flexibility is desired for instance in order to influence control and steering characteristics.

Further advantages and characteristics of the invention are apparent from the patent

claims as well as from the following description of an embodiment of the invention with reference to the enclosed drawings. In these fig 1 shows a roller skate of inline type in accordance with the invention seen from the side, fig 2-4 a part of the same roller skate seen from above, from the side and from the rear.

The inline roller skate shown in the drawings include a shoe 1, on the bottom side of which a U-shaped profile 2 is fastened with rivets 3a and 3b, so that its lateral flanges 4,5 extend vertically downwards from the shoe and constitute a longitudinal channel 6. In the channel 6 a leaf spring 7 is arranged, that in its outer ends has fork like extensions 8a and 8b between which wheels 9a and 9b are arranged. The leaf spring is made of carbon fiber and is its middle section provided with a wave like profile 10 on the side facing downwards. The walls or flanges 4,5 of the receiving channel are provided with through holes through which pins 11 can be inserted in order lockingly to grip into the wave like recesses in the profile 10 at the middle section of the leaf spring. In this way the leaf spring can be fixed and also be adjusted lengthwise in relation to the shoe by allowing the pins to be inserted into different "wave troughs". If so is desired the arranging of an additional set of holes in the sides of the channel may achieve a possibility to adjustment lengthwise for the leaf spring in relation to the shoe part with a closer spacing than the distance between two proximate waves of the profile. The two pins 11 are in one end connected to a connection piece 14 that also has a gripping part to simplify the retraction from the profile. On the other side of the profile a locking is arranged in the shape of small piece of panel 12 that can grip into recesses 13 on the extending parts of the pins on this side (if a small panel piece should be lost it is possible to make do with a rubber band).

By locating the fixing of the leaf spring approximately level with the arch some additional space may be achieved for the locking of the leaf spring in the above or some other way.

Through the above described mounting not only adjustability is obtained but it also becomes possible to remove the pins and remove the leaf spring so that an appearingly normal skiing shoe or shoe remain. By arranging part of soles at the sides of the leaf spring receiving channel it is possible to use the shoe part as an ordinary shoe when the leaf spring and the wheels have been removed. When one again want to skate with inlines the leaf spring can again quickly be mounted. Through the ease with which the leaf spring can be removed and remounted it also becomes very simple to adjust the position of the leaf spring when skating

and one can thus adapt the location after the varying need of the skating, for instance how much in a hurry one is, if one goes upwards or downwards etcetera.

In order to change the spring characteristic also rubber wedges 15a and 15b may be arranged between the spring and the profile.

If so is desired an additional a sole part may be inserted instead of the leaf spring in the channel when the inlines are used as shoes, at which the sole part can be retained with the same locking means that otherwise holds the leaf spring. In this way a larger surface is obtained and also dirt, snow and rubbish is prevented from entering into the spring receiving profile. Since the leaf spring is controlled by the profile and no play is desired the permissible variation must be kept comparatively small and it may thus be enough with comparatively small clogging of the profile to prevent mounting.

Since the number of wheels is less than otherwise normal at inlines the total resistance from the wheel bearings becomes smaller. Since further due to the springing hard wheels can be used the rolling resistance for each wheel against the ground can be reduced. The result is that the inlines according to the invention roll easily as opposed to what a man skill in the art would believe, and furthermore turning is easy. Since only two wheels are used furthermore a lighter roller skate is obtained, which result in easier skating.

When the unit comprising leaf spring and wheels has been removed from the inline skate it constitute a unit that is comparatively simple and easy to hold (the narrow middle section), which furthermore contribute to the ease with which the inlines skate can be handle.

In particular one can put them on as shoes or skishoes that are them provided with their wheels just when they are to be used as inlines.

The leaf spring is in the shown case rectangular to its cross section, but one can also consider other shapes.

Through the stable fastening and the springing, but against torsion and bending laterally very stiff leaf spring the inlines are felt as very exact and stable at the same time as they can spring in order to reduce rolling resistance and shocks.