IN-LINE ROLLER SKATE WITH FRAME INTERFACE
FIELD OF THE INVENTION
The present invention relates to in-line roller skates and more particularly to in-line roller skates having an interface.
BACKGROUND OF THE INVENTION
Over the past few years roller skating and particularly inline roller skating has enjoyed an immense resurgence in popularity. No longer limited to indoor rings specifically designed for that purpose, skating today has become an outdoor leisure activity, an economic and healthy means of transportation, and a competitive sport.
The changes in the nature of skating have necessitated appropriate changes in the design and manufacture of skates themselves. Today's skaters demand skates which are much lighter in weight and easier to control than the bi-axle quad-wheeled skates of the past.
The original design of modern in-line skates was relatively simple. Generally, such skates consisted of a wheel frame attached to a skate boot. The skate boot itself was customarily based on either an ice skate boot or a downhill ski boot. While the former had a relatively flat sole interfacing with the planar surface of the foot and was made of conventional material such as a thermoplastic rubber, the latter was typically a molded plastic boot with an integral structure.
Conventional roller skate boots comprise a boot upper attached to a sole. The sole interfaces with the plantar surface of the foot and protects it, while the boot upper surrounds and secures the remaining portions of the foot instep (e.g. dorsal portion). Soles may either be formed from a layer of a single material or from several layers of a single or different materials. In the latter case, the layers are bonded together to form a laminate. In both cases, at any particular point on the sole, the material(s) of which the sole is formed is (are) identical to those at every (or almost every) other point on the sole.
The wheel frame typically consisted of two parallel rails connected by a bridging portion to form a long inverted "U"-shaped structure. The wheels would be mounted within the frame by being rotatably mounted on the rails. The bridging portion served to connect the rails together and it was a point of attachment for the wheel frame to the skate boot too. In this respect, the bridging portion was also generally flat, would interface with the underside of the boot sole and be secured thereto by suitable fasteners, such as bolts or rivets. A relatively thin planar attachment plate might have been placed between the frame and the sole in some skates.
It has been realized that an important consequence of this construction is that the bridging portion serves as the point of force transfer between the boot and the wheel frame. However, this construction is not optimal for several reasons.
Biomechanical studies have shown that the entire weight of the body rests on three points: the heel, the first metatarsal and the fifth metatarsal. These points are thus important for the skater as they represent the points of force transmission from his body to the skate.
When the skater is in a static position, the weight is generally distributed as follows: 45% on the heel, 40% on the first metatarsal and 15% on the fifth metatarsal. During the skater's movement, the weight distribution between these points shifts. By shifting his weight between these points, the skater can control his movement. That is one of the main means for movement control. So for the skater, these points are definitely important as they represent the zones of transmission of the force necessary to his movement.
The bridging portion of conventional wheel frames however generally interfaces with the sole of the skate at two different places. The first place is a forward point generally in the ball region of the foot, and the second place is a rearward point generally in the middle of the heel portion of the foot. Thus, some of the forces generated by the skater will be wasted in the flexion of the sole about the bridging portion instead of being transmitted to the frame and to the skating surface.
It has been realized that in order to avoid wasting the skater's energy in the flexion of the sole, the sole should generally be made of rigid material. Rigid materials, however, may or may not be desired specifically at the force transmission points depending on the degree of "feel" (absorption / transmission) sought. Furthermore, it may be wished to have different levels of absorption/transmission at each of the force transmission points.
Preferably, the point of force transfer from the skater to the skate should be as near the skating surface as possible in order to allow the greatest possible control. Transferring force at the bridging portion thus represents a significant loss of control.
Thus, there is a need in the industry to provide a skate boot and an in-line roller skate allowing a more efficient transfer of force between the foot and the frame and that alleviates the drawbacks of prior art designs.
OBJECTS AND STATEMENTS OF THE INVENTION
It is thus an object of the present invention to provide a skate boot and an in-line roller skate with such a design that it can allow a more efficient transfer of force between the skater's feet and the skating surface as compared with conventional boots.
A further aim of the present invention is to provide a skate boot and an in- line roller skate that offers the possibility to use only one size of frame with a plurality of boot sizes.
As embodied and broadly described herein, the present invention provides a roller skate comprising a frame having substantially parallel rails, a plurality of wheels rotatably mounted to said frame, a boot connected to an interface, said interface being connected to said frame, wherein the frame is provided with bridging portions connecting the substantially parallel rails of the frame, the interface being provided with projections extending opposite from said boot and connected to said frame through connection points provided on the rails.
With such a design, the skater's force or energy is more easily transmitted to the skate frame while providing improved efficiency. Moreover, the use of an interface allows using a plurality of boot sizes with only one frame size. A plurality of interface sizes permit to adapt the frame the any boot size. The manufacturer can thus produce only one frame, and save costs.
The connection points are preferably between the bridging portions and the opposite edge of the rails. The lower the connection, the more energy will be transmitted to the rolling surface, without being dissipated.
Advantageously, the frame comprises a first surface and a second surface, respectively adapted for connection with a first portion and a second portion of the sole of the boot. This provides easy connection and ergonomics. The projections preferably extend from the surfaces. These surfaces may be connected together. The resulting interface is very simple and cost effective. For instance, it may be produce by traditional molding techniques.
The wheel frame comprises two parallel rails which are interconnected by bridging portions. The bridging portions need not however extend the length of the rails owing to the presence of the interface. The bridging portions need be of sufficient length to provide for a stable interconnection between the rails.
The interface provides for the attachment of the skate boot to the wheel frame. The interface comprises a forward generally smooth surface designed to interface with the area of the sole corresponding to the ball area of the foot. The forward surface is of such dimensions so as to extend across the sole and encompass the first and fifth metatarsals. Extending generally perpendicular from the forward surface are spaced apart projections. The distance between the projections is such that the rails of the wheel frame may be received therein. Near the end of the projections, there is provided a means for securement to the wheel frame along the side of the rail (E.g. by passing a bolt through the projections and the rails). The interface further comprises a rear surface similar to the forward surface which is adapted to interface with the portion of the sole corresponding to the heel, and having similar projections for securement to the wheel frame.
Advantageously, the rear surface further comprises an extension up from the surface adapted to receive and secure the heel of the boot. The surfaces are interconnected by a connecting member.
The entire interface is constructed from a rigid lightweight material, preferably a metal. Advantageously, the member interconnecting the forward and rear surfaces is provided with reinforcements to further prevent flexion. The skate of the present invention is thus extremely rigid, thus minimizing torsional flexion and corresponding energy loss, while being light in weight. In addition, improved control is provided.
A further benefit of this construction is reduced cost of manufacture of a line of skates according to this design. Conventionally, as the skate frame itself was designed to interface with the boot, skate frames having different dimensions and characteristics (e.g. long, short, 4-wheeled, 5-wheeled) needed to be manufactured for approximately each size of boot. In skates of the present design, however, it is the interface which adapted to interface with the boot, not the wheel frames. Thus, the interfaces designed to interface with different boot sizes may nonetheless have standardized frame-mating projections. Accordingly, a single wheel frame (of whatever characteristic) may be attached to boots of many sizes.
Other objects and features of the invention will become apparent by reference to the following description and the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will further be described, by way of example only, of preferred embodiments, reference being made to the accompanying drawings, in which:
Figure 1 is a side elevational exploded view illustrating a roller skate according to the present invention;
Figure 2 is a perspective view of the skate of figure 1.
Throughout the drawings, the same reference numerals designate identical or similar elements. In the drawings, preferred embodiments of the invention are illustrated by way of example. It is to be expressly understood that the description and drawings are only for purposes of illustration and as aid to understanding, and are not intended to be a definition of the limits of the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to figure 1 , there is a roller skate 10 comprising a skate boot 12 and interface 14, and a wheel frame 16. The skate boot 12 comprises a boot upper 18 and a sole 20. In this example the sole 20 is in the form of an inverted shell which will receive the foot of the skater. The sole 20 is constructed of a rigid plastic material or rubber and is provided with reinforcements 22 of a more rigid material in the area of the ball of the foot and the instep, all by conventional means. The boot upper 18 is constructed according to known methods.
The interface 14 has a forward surface 24 and a rear surface 26 interconnected by a connecting member 28. Extending from the surfaces are projections 30 and 32 respectively adapted to receive and secure the wheel frame 16. Also extending from the rear surface 26 is a heel retaining portion 34. The connecting member 28 is provided with reinforcements 36. The interface is manufactured by conventional methods from a rigid material, preferably a metal. The interface is secured to the sole 20 by conventional means.
The wheel frame 16 comprises two parallel rails 38 interconnected by bridging portions 40. Wheels 42 are conventionally rotatably mounted within the frame 16. The frame 16 is secured to the interface 14 by conventional means (such as a bolt) at points 44. The frame is constructed of lightweight conventional materials in accordance with known methods. The above description of preferred embodiments should not be interpreted in a limiting manner since other variations, modifications and refinements are possible without departing from the spirit of the present invention. The scope of the invention is defined in the appended claims and their equivalents.