In recent years, roller skating and in-line skating have become extremely popular. Many participants in these sports have developed an interest in what is known as "aggressive" or "extreme" skating. Such skating includes jumping, flipping, sliding across raised surfaces, sliding down rails, and other similar types of maneuvers.
In-line skates generally have a frame and a boot coupled to the frame. The boots of many in-line skates include hard outer shells covering portions of a soft inner liner. Typically, the frame of a skate is made of relatively rigid plastic or metal and has a platform to which the sole of a boot is connected. The frame also typically includes two spaced-apart rails that extend below the platform and define an elongated channel in which four tandemly arranged wheels can be rotatably mounted.
Features desired by aggressive skaters include a low frame stance, rockering ability, and the ability to replace the inner two wheels with wheels that are smaller than the outer two wheels while maintaining ground contact with all of the wheels. Typically, in-line skates use eccentric spacers to adjust the positioning of the various wheels. One example of an eccentric spacer is disclosed in commonly assigned U.S. Pat. No. 5,048,848.
One desirable feature of an eccentric spacer is to maintain a low frame stance with various wheel sizes. It is also desirable for eccentric spacers to be configured to permit a skater to use a larger diameter wheel in the front and the back of the skate and to use a smaller diameter wheel in the middle two wheel positions of the frame while maintaining ground contact with all of the wheels. Smaller wheels in the middle two positions are desirable because they provide a greater distance between the wheels in the middle of the frame for grinding.
It is also desirable to have a spacer that permits rockering. Rockering is a term used to indicate that the lowest circumferential points of the front most and the rear most wheels are vertically higher from the ground than the lowest circumferential points of the wheels between the front most and rear most wheels of the skate. Thus a curved plane of ground contact is formed to permit "rockering" by the skater.
The present invention provides numerous advantages over the over the prior art, as will be understood with reference to the summary, the detailed description and the drawings.