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A method and apparatus for reducing friction in a cam buckle for tightening a strap. The cam buckle includes a frame, a brake member, a roller member, a biasing element and a webbed strap. The brake member includes a serrated surface and is rotatably coupled to the frame and pivotal about a first ax

A method and apparatus for reducing friction in a cam buckle for tightening a strap. The cam buckle includes a frame, a brake member, a roller member, a biasing element and a webbed strap. The brake member includes a serrated surface and is rotatably coupled to the frame and pivotal about a first axis. The roller member is rotatably coupled to the frame about a second axis, wherein the first axis and the second axis are substantially parallel to each other. The biasing element is operable to bias the serrated surface of the brake member toward the roller member. The webbed strap is formed from a polymeric material and is operable to be biased between the serrated surface and the roller member so that the brake member biases the webbed strap against the roller member. With this arrangement, when the webbed strap is placed in tension, such tension is maintained by preventing movement of the webbed strap in one direction and allowing movement in a second direction to increase the tension. The roller member is operable to rotate with movement of the webbed strap in the second direction to increase the tension in the webbed strap.

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1. A cam buckle configured to reduce friction for tightening a strap, the cam buckle comprising:a frame; a brake member at having a contoured friction surface, said brake member being rotatably coupled to said frame and pivotal about a first axis, and including a brake roller having unidirectional r

1. A cam buckle configured to reduce friction for tightening a strap, the cam buckle comprising:a frame; a brake member at having a contoured friction surface, said brake member being rotatably coupled to said frame and pivotal about a first axis, and including a brake roller having unidirectional rotation; a roller member rotatably coupled to said frame about a second axis, said second axis being substantially parallel said first axis; a biasing element operable to bias said brake member toward said roller member and against the strap; and a webbed strap operable to be biased between said contoured friction surface and said roller member so that said brake member urges said webbed strap against said roller member when placed in tension so as to maintain said tension by preventing movement of said webbed strap in one direction and allowing movement in a second direction to increase said tension; wherein said roller member and said brake roller are operable to rotate with movement of said webbed strap in said second direction to increase said tension in said webbed strap. 2. The cam buckle of claim 1, wherein said roller member comprises a shaft coupled to said frame and a cylinder rotatable around said shaft.3. The cam buckle of claim 2, wherein said roller member includes bearings disposed in said cylinder and operable to rotate with said cylinder around said shaft.4. The cam buckle of claim 1, wherein said roller member comprises a cylinder with recesses defined in opposing ends of said cylinder, said cylinder rotatable around nubs extending from and disposed in said frame.5. The cam buckle of claim 1, wherein said tension in said strap is substantially limited only by rolling contact friction in said roller member with respect to a pulling force applied to said webbed strap in said second direction.6. The cam buckle of claim 1, wherein the roller member comprises a substantially smooth surface configured to be at least partially in contact with the webbed strap.7. The cam buckle of claim 1, wherein said roller member comprises an abrasive surface configured to be at least partially in contact with the webbed strap.8. The cam buckle of claim 1, wherein said contoured friction surface of said brake member comprises serrations slantedly oriented so that said webbed strap passes over said serrations in said second direction and is prevented from passing over said serrations in said first direction.9. The cam buckle of claim 1, wherein said roller member comprises an axially concave surface configured to be in contact with the webbed strap.10. The cam buckle of claim 1, wherein said roller member comprises an axially convex surface configured to be in contact with the webbed strap.11. The cam buckle of claim 1, wherein said roller member comprises a grooved surface configured to be at least partially in contact with the webbed strap.12. The cam buckle of claim 11, wherein said grooved surface collectively comprises a pattern configuration operable to substantially maintain a centered position of said webbed strap during movement of said webbed strap in said second direction.13. The cam buckle of claim 1, wherein said frame includes tabs extending inward at opposing positions from said frame to substantially maintain a centered position of said webbed strap during movement of said webbed strap in said second direction.14. The cam buckle of claim 1, wherein said webbed strap comprises a woven high-strength polymeric material.15. The cam buckle of claim 1, wherein said webbed strap comprises at least one of a polypropylene material and a polyethylene material.16. The cam buckle of claim 1, wherein said brake member includes a sprag member operable with said brake roller to provide said unidirectional rotation so as to prevent movement of said webbed strap in said one direction and to maintain said tension in said webbed strap.17. A cam buckle configured to reduce friction for tightening a webbed strap, the cam buckle comprising:a frame; a roller member rotatably coupled to said frame; a brake member movably coupled to said frame, including a second roller having unidirectional rotation; and a biasing element operable to bias said brake member toward said roller member with the webbed strap therebetween; wherein said roller member acts in conjunction with said brake member to capture the webbed strap between said brake member and said roller member when the webbed strap is placed in tension by preventing movement of the webbed strap in one direction and allowing movement in a second direction; and wherein said roller member and said second roller are operable to rotate with movement of the webbed strap in said second direction to increase said tension in the webbed strap. 18. The cam buckle of claim 17, wherein said brake member includes a sprag member operable with said second roller to provide said unidirectional rotation so as to prevent movement of said webbed strap in said one direction and to maintain said tension in the webbed strap.19. A cam buckle for tightening a strap, comprising:a frame; a first roller, rotatably coupled to the frame; an elongate strap, disposed against the first roller; a cam, pivotally coupled to the frame and disposed against the strap opposite the first roller, the cam including a second roller having unidirectional rotation, configured to secure the strap between the second roller and the first roller to resist movement of the strap in a first direction, and to allow movement of the strap in a second direction, the first and second rollers being configured to rotate with movement of the strap in the second direction; and a biasing element, configured to bias the cam toward the first roller and the strap. 20. The cam buckle of claim 19, further comprising a sprag, configured to resist rotation of the second roller corresponding to movement of the strap in the one direction.21. A cam buckle for tightening a strap, comprising:a frame; a roller, rotatably coupled to the frame, having an axially-curved surface; an elongate strap, disposed against the first roller; a cam, rotatably coupled to the frame and disposed against the strap opposite the roller, having an axially-curved, contoured friction surface substantially congruent to the axially curved surface of the roller, the cam being configured to secure the strap between the cam and the roller to resist movement of the strap in a first direction, and to allow movement of the strap in a second direction; and a biasing element, configured to bias the cam toward the roller and the strap; the roller being configured to rotate with movement of the strap in the second direction. 22. The cam buckle of claim 21, wherein the laterally-curved surface of the roller is convex, and the laterally-curved surface of the cam is concave.23. The cam buckle of claim 21, wherein the laterally-curved surface of the roller is concave, and the laterally-curved surface of the cam is convex.