SHIELD PLATE OF WHEEL ROLLER BEARING OF ROLLER SKATE

Background of the invention

This invention relates to a shield plate to be installed for protecting a wheel roller bearing of a roller skate the purpose of which plate is to protect the wheel roller bearing of the roller skate from contamination and to facilitate the servicing of the bearing.

Solutions are known for protecting a wheel roller bearing of a roller skate. In known solutions, a shield plate is generally installed directly to the wheel so that the shield plate rotates along with the wheel of the roller skate. Solutions according to known shield plates require more fixing parts with which the shield plate is fixed to a wheel or, alternatively, to a rail of the roller skate. The fixing of the shield plate to the wheel or the rail of the roller skate can also be performed by gluing or by a similar manner.

From specification US 5590935 is known a shield plate for protecting the wheel bearing of a roller skate which plate is disc-shaped and which rotates along with the wheel. The shield plate has a hole for the shaft of the wheel, and the outer diameter of the shield plate is such that the shield plate covers the whole bearing housing. In the solution according to the specification, the shield plate is fixed with an adhesive to the wheel.

Solutions according to prior art for protecting the wheel bearing of the roller skate include disadvantages. In bearing shield plates according to known solutions, dirt can easily access the bearing during use. The contamination of the bearing is harmful as it shortens the lifetime of the bearing and weakens the properties of the bearing. For this reason, the bearings have to be washed and cleaned at short intervals, and cleaning and washing bearings is laborious and time-consuming, because there are several bearings in the roller skate. Furthermore, when servicing bearings, dirt can also access the bearing during the service operations.

Many bearing shields according to known solutions also have several parts for the fixing, and the removing or fixing of the bearing shields from the wheel requires special tools.

Brief description of the invention

The apparatus according to the invention is characterised by what is stated in the characterising part of claim 1.

Furthermore, the apparatus according to the invention is characterised by what is stated in the appended dependent claims 2-5.

The now presented solution according to the invention has some considerable advantages compared to known solutions.

The solution according to the invention for protecting a wheel bearing of a roller skate with a shield plate provides a good and functional protection for preventing the contamination of the bearing and thus for extending the lifetime of the bearing. The shield plate is easy to install to/remove from the wheel, and no separate fixing parts are required in it, because it is pressed tightly and sturdily between the bearing case and the rail of the roller skate.

Cleaning and lubricating bearings is facilitated, because the bearings can be cleaned and lubricated without removing them from the wheel.

When utilising the bearing shield according to the invention, also open bearings instead of closed bearings can be used, because the shield plate protects the bearings so well that there is no need for the bearings to be closed.

Furthermore, the shield plate is easy and cheap to manufacture from commonly used materials suitable for use in the most generally used wheels of roller skates.

There is also no need for separate tools for servicing the bearing, because it is possible to start servicing the bearing by removing the shield plate, whereby the inspection of the condition of the bearing and the cleaning and lubrication of the bearing can be performed. When removing the wheel from the rail of the roller skate, no dirt accesses the bearing even during the removal process as the shield plate protects the bearing.

Brief description of the figures

The invention will now be described in more detail by means of examples with reference to Figs. 1-2, in which Figs. 1a, 1b and 2 show a shield plate and its location in a wheel of a roller skate.

Detailed description of the invention

Fig. 1a is a simplified perspective view of the fixing of a wheel 1 of a roller skate on a rail of the roller skate by means of a shaft 11. On both sides of the rail 13 of the roller skate there are holes 16 of which there are several successively depending on the number of the wheels of the roller skate.

A shield plate 2 protects the wheel bearing (not shown in the figure) of the roller skate which plate covers a portion of the wheel 1 of the roller skate seen from the side, as shown in Fig. 1 b.

Fig. 2 is a top plan view of a cross section of the fixing of a shield plate 2 intended for protecting the wheel bearing of the roller skate to the wheel of the roller skate. The shield plate 2 protecting the wheel roller bearing of the roller skate is installed outside the roller bearing in such a manner that the shield plate rests (is fixed) against the inner race 10 of the bearing and the rail 13 of the roller skate. The shield plate 2 of the bearing has a fixing lug 9 by means of which the shield plate remains in its place, because the lug rests against the inner race 10 of the bearing. The wheel/rail can also have attachments (not shown in the figure) with which the shield plate is fixed to the wheel and the rail.

The shield plate extends over the outer race 7 of the roller bearing so that it covers a portion of the wheel 1.

On the inner race 10 of the bearing of the shield plate rests a sleeve-shaped piece 8 which prevents the inner race of the bearing from moving, keeping the inner races of the bearing at a desired distance from each other. The outer race 7 of the bearing is supported by an adapter piece 12 which prevents the outer race of the bearing from moving.

In addition to the lug 9 supporting the inner race of the bearing, to the shield plate 2 (on its inner surface) have been formed projections 3, 4 and 5 the purpose of which is to prevent the access of dirt and litter (though gap A) between the wheel and the shield plate and further to the roller bearing. The projections can be located on the edge or near the edge of the shield plate, in the middle of the shield plate or at a desired point in the shield plate. The projections can be parallel to the shield plate or perpendicular against the shield plate or at a certain angle in relation to the shield plate. The width of the projections can vary, and different projections can be of different width.

The wheel 1 of the roller skate has a recess 15 which is dimensioned so that the projections fit in the recess without touching the wheel 1. In an advantageous case, there is a gap as small as possible between the projections and the wheel for dirt and litter not to access between the wheel of the roller bearing and the shield plate.

In the hole 16 of the rail of the roller skate is placed the shaft 11 which is fixed in its place with a fixing screw 6. The shaft 11 is threaded with threads 14 on the inside, and the fixing screw 6 has corresponding threads on its outer surface. By tightening the fixing screw 6, it is possible to define how tightly the shield plates are pressed against the rail 13 of the roller skate and the inner race 10 of the bearing.

When tightening with the fixing screw 6, the shield plate is centred to the accurate point by means of the projections against the shaft 11.

After removing the fixing screw 6, the shaft 11 can be easily pulled away from the rail, after which the wheel, in which the shield plate is still fixed by means of the projection 9, can be easily removed from the rail. As the shield plate is still on the wheel, it protects the bearing from contamination during the whole removal process and also after the removal. Now it is easy to remove the shield plate from the wheel for inspecting the roller bearing or for servicing the roller bearing.

The shield plate 2 is manufactured of plastic or plastic composites, but it can also be manufactured of metal, metal alloys or other suitable materials.

It is well known by those skilled in the art that the different embodiments of the invention are not solely limited to the examples described above, and thus they may vary within the scope of the appended claims.

Alternatively, the solution according to the invention for preventing the contamination of the roller bearing can also be realised so that one or more grooves are formed to the shield plate whereby, correspondingly, projections are formed to the wheel for each groove. The grooves can then be located on the inner surface of the shield plate, on its inner race and/or outer race and/or between the inner race and the outer race.