The present invention relates to roller skis. Roller skis are used by skiers in the non snow seasons, mainly for training by competitive cross country and Alpine skiers. Roller skis have a frame which supports the foot, generally with one wheel in front and one wheel in the back. Mounted to the frame is a ski binding for attaching the ski boot to the frame as shown in
Roller skis have been commercially available for over 35 years but, until the present invention, no one has offered a leg activated brake for conventional roller skis. Prior art includes hand activated brakes and using ski poles to stop the skis. Braking by a ski pole is unsafe and not effective. To brake with a hand activated brake is difficult without the skier loosing his balance and in an emergency the brake cannot be activated quickly enough as the skier has to reach, with his hand holding the ski pole, the brake pull handle which is generally attached to the skiers leg as depicted in
In order for the skier to preserve balance the skier should have both hands on the ski poles and the body should be in a balanced ski position. For safety and rapid braking in an emergency situation, the brake should be able to be activated by the leg when the skier is in a stable position. This position is often referred to as the “Telemark” position and is shown in
U.S. Pat. No. 6,082,768 describes a leg activated brake for roller skis, where the brake is an integral part of the foot platform and the roller ski design. U.S. Pat. No. 4,033,596 describes a foot activated brake for roller skis with two, side by side, wheels in the back, but the patent does not provide a method for the brake to be adjusted for different wheels, ski bindings, ski boots, roller ski frames and different user's anatomy. Because U.S. Pat. No. 4,033,596 did not provide solutions for these variables, no commercial leg activated brakes were produced for conventional roller skis prior to the invention described herein.
U.S. Pat. No. 5,924,704 describes another foot activated brake for roller skis but, as in U.S. Pat. No. 6,082,768, the brake is not suitable for mounting to conventional roller ski frames.
The main object of the invention is to provide a braking system for conventional roller skis that can be leg activated only when the skier is in a stable position and a brake that does not touch any part of the users anatomy except when braking. The brake structure has members for vertical and horizontal adjustments so the brake structure can be adapted to a variety of boot designs, boot sizes, frame structures, ski binding mounting locations, wheel sizes and the user's anatomy.
Another objective of the invention is to provide a method of mounting the brake to the foot supporting frame of conventional roller skis in such a manner that the frame retains its structural integrity and the brake structure does not interfere with the ski binding or the ski boot.
The brake structure of the invention is such that it can be mounted to the roller ski frame with conventional screws and it utilizes minimal space. In one embodiment the brake can also be folded across the ski binding.
Other advantages of the invention will be apparent from the following descriptions of the embodiments thereof and from the claims.
FIG.14 is a side view of the user's leg and foot position with the heel up in classic and skate technique.
Referring to
Mounted to the frame is ski binding 16, to which is attached ski boot 4.
The roller ski further includes a U shaped bottom support member 17, which is fastened to the frame 1. Pivotally mounted to bottom support member 17, via pivot pin 8, is the lower member 6 to which is mounted the upper articulated member 7 via mounting screws 10.
Mounted to member 7 is the yoke member 14 which is fastened by mounting screws 13. Mounted to the lower member 6 is brake pad 5. Mounted to U shaped support member 17 and to member 6 is extension spring 15.
When the brake is in the upward position for braking as shown in
For proper balance the binding 16, must be mounted in a specific position which is dependent on the boot size, the ski weight and the length of the ski.
Referring to
Since ski bindings must be mounted to the top of the frame, all roller ski frames are designed to accept standard self tapping mounting screws.
Mounted to the U shaped support 17, via threaded pivot pin 8 and nut 22, is lower member 6 which is held in the upright position by the tension of extension spring 15 and by the spring loaded plunger 9, which contacts one side of member 6 and is fastened to U shaped support 17.
Attached to member 6 is brake pad 5 which can be moved to different vertical positions on member 6 via screw holes 21 and 21a which are vertically located, in pairs, on member 6. In one embodiment brake pad 5 has threaded holes to accept screws 20 and 20a. Brake pad 5 is constructed of heat treated steel with a minimum hardness of Rockwell 50C.
In the embodiment shown, spring loaded plunger 9 is a standard commercially available unit which is fastened to the U shaped member 17. Spring 15 is attached to U shaped member 17 and to lower member 6 as shown in
In the design depicted, member 7 is fastened to member 6 by socket screws 10. Lower member 6 has clearance holes for the screws 10, while the upper member 7 contains commercially available press fit nuts 18, which accept the socket screws 10.
Member 7 is angularly adjusted, with respect to to lower member 6, to fit the leg anatomy of different users.
When tightened, the clamping force generated by the socket screws 10 and nuts 18, joins member 7 and member 6 so they become an integral unit rotating about pivot pin 8.
In the embodiment depicted, yoke assembly 14 is attached to upper member 7 by socket screws 13 which are threaded into nuts 11 of member 7. Yoke 14 has several holes 12, for greater adjustability of the yoke with respect to the users leg anatomy. In one embodiment yoke assembly 14 is configured so it can contact the leg in a lower position by rotating yoke 14 180 degrees and fastening the yoke to member 7 as shown in