This invention relates to the field of roller skates and, particularly, to an improved skate with canted, large diameter wheels.
Various designs of roller skates have been developed over the years. At the present time, xe2x80x9cin-linexe2x80x9d skates are particularly popular. This type of skate has a plurality of small-diameter wheels aligned in a longitudinal direction beneath the sole of the skater""s foot. A number of advantages are claimed for this design of a skate. However, the small diameter of the wheels inherently limits the speed that can be achieved and limits the use of the skates to relatively smooth surfaces.
Among alternative skate designs, skates with large-diameter wheels have been proposed for over a century. For example, U.S. Pat. No. 89,833 discloses a skate with a single wheel of large diameter for use in skating on fields and other uneven surfaces. This skate, and many similar prior art designs, places the wheel to the outside of the skater""s foot. While this allows a lower center of gravity than if the wheel were to be located entirely below the skater""s foot, undue strain is placed on the skater""s ankles because of the lateral offset between the center line of the skater""s foot and the point of contact between the wheel and the ground. One solution to this problem is to mount the wheel at an angle with respect to vertical so that the point of contact with the around will be directly below the skater""s foot. Such a design for a single-wheeled skate is shown, for example, in U.S. Pat. No. 2,931,012.
Single-wheeled skates are, of course, inherently unstable. A design for a skate with two large diameter wheels is shown in U.S. Pat. No. 3,885,804 to Cudmore. In this design, two large, canted, equal-sized wheels are mounted on axles extending outwardly from a rigid sole-plate. As disclosed by Cudmore, the canted wheels contact the ground directly beneath the center line of the sole-plate. The wheels are dished with their concave sides facing toward the sole-plate so that a portion of the sole-plate extends into the wheel concavities to permit the sole-plate to be positioned very close to the ground. Cudmore""s design provides a reasonably stable skate in comparison to many of the prior art designs; however, development of the present invention has yielded improved stability and responsiveness over the design of Cudmore. Furthermore, the dished wheels used by Cudmore to achieve a low center of gravity inherently limit the ability to turn sharply since the outside surfaces of the wheels will contact the ground when the skate leans in a sharp turn. The present invention overcomes this disadvantage by positioning the wheels so that dishing is not necessary to achieve an acceptably low center of gravity.
The present invention is a two-wheeled roller skate with canted wheels. In a preferred embodiment, the axle for the forward wheel is located well forward of the ball of the foot, approximately in line with the skater""s toes. The axle for the rear wheel is located at the rear of the skater""s heel. The wheels are canted so that the front wheel contacts the ground slightly outside of the center line of the skater""s foot and the rear wheel contacts the ground slightly inside of the center line. This contact geometry permits the use of a relatively small diameter front wheel and thereby allows the sole of the skate to be positioned close to the ground. In plan projection, the axles are preferably non-parallel in order to provide steering correction. The amount of steering correction desirable will depend on the skater""s skill and the nature of the skating activity. In alternative embodiments,.the present invention incorporates novel braking mechanisms.