Friction hinge with clutch-based resistance

1. A hinge comprising:

a shaft;

a hinge leaf engaged with the shaft;

a band clamped around the shaft for rotation about the shaft and pivotal movement relative to the hinge leaf; and

a locking mechanism disposed between the band and the shaft, the locking mechanism comprising a collar disposed between the shaft and the band, the locking mechanism being configured to lock and unlock the collar to the shaft;

wherein the locking mechanism is configured such that rotation of the band or the shaft in a first clockwise direction locks the collar to the shaft for frictional movement of the band about the shaft at a first resistance level, and

wherein the locking mechanism is further configured such that rotation of the band about the shaft in a second counter-clockwise direction different from the first clockwise direction unlocks the collar from the shaft for frictional movement of the band about the shaft at a second resistance level lower than the first resistance level, wherein the first clockwise direction is relative to a view of a first end of the shaft, and the second counter-clockwise direction is relative to the view of the first end of the shaft.

2. The hinge of claim 1 , wherein the collar is not disposed between the band and the shaft for a portion of an axial length of the band.

3. The hinge of claim 1 , wherein:

the shaft has a first section and a second section with a smaller diameter than the first section; and

the collar is disposed in the second section and not disposed in the first section.

4. The hinge of claim 3 , wherein the band is frictionally engaged with the shaft in the first section.

5. The hinge of claim 1 , wherein the band comprises a gap that extends an axial length of the band to form a cantilever spring about the shaft.

6. The hinge of claim 1 , wherein the locking mechanism comprises a roller pin.

7. The hinge of claim 6 , wherein the shaft comprises a notch in which the roller pin is disposed.

8. The hinge of claim 7 , further comprising a spring disposed in the notch to bias the roller pin toward the collar.

9. The hinge of claim 1 , wherein the hinge leaf is configured as part of a cam arrangement.

10. A hinge comprising:

a shaft;

a cam attached to the shaft, the cam comprising a hinge leaf extending radially outward from the shaft;

a cam follower comprising a band, the band rotatably clamped around the shaft for rotation about the shaft and pivotal movement relative to the cam; and

a clutch disposed between the band and the shaft, the clutch comprising a collar disposed between the shaft and the band;

wherein the clutch is configured such that rotation of the band about the shaft in a first counter-clockwise direction locks the collar to the shaft for frictional movement of the band about the shaft at a first resistance level,

wherein the clutch is further configured such that rotation of the band about the shaft in a second clockwise direction different from the first counter-clockwise direction unlocks the collar from the shaft to allow the collar to rotate about the shaft for frictional movement of the band about the shaft at a second resistance level lower than the first resistance level, and

wherein unlocking the collar from the shaft includes complete decoupling from the shaft.

11. The hinge of claim 10 , wherein the collar is not disposed between the band and the shaft for a portion of an axial length of the band.

12. The hinge of claim 10 , wherein:

the shaft has a first section and a second section with a smaller diameter than the first section; and

the collar is disposed in the second section and not disposed in the first section.

13. The hinge of claim 10 , wherein the clutch comprises a roller pin.

14. An electronic device comprising:

a chassis;

a stand supporting the chassis; and

a hinge pivotably attaching the chassis and the stand, the hinge comprising:

a shaft comprising a notch;

a band clamped around the shaft for rotation about the shaft;

a collar disposed between the shaft and the band; and

a roller pin disposed in the notch;

wherein rotation of the band about the shaft in a first clockwise direction wedges the roller between the collar and the shaft to fix the collar in place for frictional movement of the band about the shaft at a first resistance level, and

wherein rotation of the band about the shaft in a second counter-clockwise direction different from the first clockwise direction un-wedges the roller pin to allow the collar to rotate about the shaft for frictional movement of the band about the shaft at a second resistance level lower than the first resistance level, wherein the first clockwise direction is relative to a first end of the shaft, and the second counter-clockwise direction is relative to the first end of the shaft.

15. The electronic device of claim 14 , wherein the collar is not disposed between the band and the shaft for a portion of an axial length of the band.

16. The electronic device of claim 14 , wherein:

the shaft has a first section and a second section with a smaller diameter than the first section; and

the collar is disposed in the second section and not disposed in the first section.

17. The electronic device of claim 14 , wherein the hinge further comprises a cam attached to the shaft.

18. The electronic device of claim 17 , wherein the hinge further comprises a link extending radially outward from the band, the link and the band acting as a cam follower relative to the cam.

19. The claim 1 , wherein unlocking the collar from the shaft includes complete decoupling from the shaft.

20. The hinge of claim 10 , wherein the first clockwise direction is relative to a view of a first end of the shaft, and the second counter-clockwise direction is relative to the view of the first end of the shaft.