Apparatus for twist-to-lock retention of a wheel

1. A quick release assembly engageable with an enclosed dropout of a bicycle comprising:

an axle having a first non-cylindrical end portion, a cylindrical central portion, and a second non-cylindrical end portion, wherein a diameter of one of the first non-cylindrical end portion and the second non-cylindrical end portion is larger than the diameter of the cylindrical central portion;

an insert having a non-cylindrical outer profile configured to be retained in a non-cylindrical opening, wherein the insert has a cam surface disposed therein and wherein the insert is sized to retain one of the non-cylindrical end portions of the axle therein; and

a shaft sized to pass through the axle and having a cam follower on a first end and a handle on a second end, wherein the cam follower is configured to form a locking engagement with the cam surface of the insert upon an axial rotation of the handle.

2. The quick release assembly of claim 1 further comprising a tensioning device affixed between the first non-cylindrical end portion of the axle and the handle, the tensioning device configured to impart a reaction force on the second end of the shaft to maintain a locking force when the cam follower is engaged with the cam surface of the insert.

3. The quick release assembly of claim 1 wherein the insert is configured to be retained in a non-cylindrical dropout located on both a first leg portion and a second leg portion of a front fork assembly of a bicycle.

4. The quick release assembly of claim 1 wherein the cam follower forms a locking engagement with the cam surface of the insert within a single rotation of the shaft.

5. The quick release assembly of claim 4 wherein locking engagement of the cam follower with the cam surface of the insert is achieved with a rotation of the shaft of less than or equal to 180 degrees.

6. The quick release assembly of claim 1 wherein the axle is sized to fit through a hub assembly of a bicycle wheel.

7. The quick release assembly of claim 6 wherein the cylindrical central portion of the axle has a diameter of 12 mm, 15 mm, or 20 mm.

8. The quick release assembly of claim 1 wherein the cam surface disposed in the insert is removably affixed to an interior surface of the insert.

9. The quick release assembly of claim 8 wherein the cam surface is formed of a material having greater wear resistance than the material from which the insert is formed.

10. The quick release assembly of claim 1 wherein the cam surface is ramped to allow the cam follower of the shaft to axially follow thereon during rotation of the shaft.

11. The quick release assembly of claim 1 wherein the tensioning device is one of a Belleville washer, a set of Belleville washers, a spring, or wherein the shaft is composed of an elastic material.

12. An apparatus for retaining a bicycle wheel, the apparatus comprising:

a hollow axle having a first end portion and a second end portion, the first end portion configured to be retained within a first enclosed dropout of a bicycle assembly;

a dropout insert configured to retain the second end portion within a second enclosed dropout of the bicycle assembly;

a cam insert affixed within the dropout insert; and

a shaft sized to travel through the hollow axle, the shaft having a cam follower on a first end and a handle and tensioning assembly on a second end, wherein the cam follower is configured to fixedly engage the cam insert upon less than a single rotation of the shaft.

13. The apparatus of claim 12 wherein both the first end portion and the second end portion of the hollow axle are non-cylindrical in shape.

14. The apparatus of claim 12 wherein cam follower is configured to fixedly engage the cam insert upon a rotation of shaft that is less than or equal to 180 degrees.

15. The apparatus of claim 12 wherein the hollow axle is sized to pass through a bicycle wheel hub.

16. An assembly for securing a wheel to a bicycle, the assembly comprising:

a removable insert configured to be affixed within a first non-cylindrical dropout of a bicycle, the removable insert having a ramped cam surface disposed therein;

an axle having a first non-cylindrical end portion and a second non-cylindrical end portion, wherein the first non-cylindrical end portion is configured to mate with an internal surface of the removable insert and the second non-cylindrical end portion is configured to mate with a second non-cylindrical dropout of the bicycle; and

a skewer configured to travel through the axle, the skewer having a cam follower on a first end and a handle on a second end, wherein the cam surface of the skewer is configured to lockingly engage the ramped cam surface of the removable insert upon less than one full axial rotation of the handle.

17. The assembly of claim 16 wherein the assembly further comprises a tensioning device located substantially adjacent to the handle.

18. The assembly of claim 17 wherein the single tensioning device comprises one of a Belleville washer, a set of Belleville washers, a spring, or wherein the skewer is composed of an elastic material.

19. The assembly of claim 16 wherein the cam surface is removably affixed within the removable insert, the cam surface formed of a material different than the material of the removable insert.

20. A quick release assembly for a bicycle comprising:

an axle having a first non-cylindrical end portion, a cylindrical central portion, and a second non-cylindrical end portion, wherein a diameter of one of the first non-cylindrical end portion and the second non-cylindrical end portion is larger than the diameter of the cylindrical central portion;

a shaft sized to pass through the axle and having a retention surface on a first end and a handle on a second end; and

an insert configured to be retained in a non-cylindrical, thru-axle dropout and having a shaft interface therein, wherein the retention surface of the shaft is configured to form a locking engagement with the shaft interface of the insert upon an axial rotation of the handle.