Hinge mechanism

1. A hinge mechanism for a foldable electronic device having a first body and a second body, comprising:

a hinge suitable to be fixed on the first body;

a pivot part pivoted to the hinge and suitable to be connected to the second body;

a friction part connected to the pivot part and selectively contacting the hinge, wherein when the pivot part rotates relative to the hinge to drive the first body to rotate from a close position to an open position relative to the second body, the friction part does not contact the hinge; and when the pivot part rotates relative to the hinge to drive the first body to rotate from the open position to the close position relative to the second body, the friction part contacts the hinge to limit a rotation of the pivot part on the hinge; and

a rotation part telescoped on the hinge and contacting the friction part, wherein when the pivot part rotates relative to the hinge to drive the first body to rotate from the close position to the open position relative to the second body, the rotation part rotates with the hinge to drive the friction part to move far away from the hinge, so that the friction part does not contact the hinge; and when the pivot part rotates relative to the hinge to drive the first body to rotate from the open position to the close position relative to the second body, the rotation part drives the friction part to move towards the hinge, so that the friction part contacts the hinge and clamps the hinge tightly.

2. The hinge mechanism of claim 1 , wherein when the pivot part rotates relative to the hinge to drive the first body to rotate from the open position to the close position relative to the second body, the friction part contacts the hinge and provides a friction to the pivot part to limit the rotation of the pivot part on the hinge.

3. The hinge mechanism of claim 2 , wherein the friction part has a contact portion, when the pivot part rotates relative to the hinge to drive the first body to rotate from the close position to the open position relative to the second body, the contact portion is far away from the hinge; and when the pivot part rotates relative to the hinge to drive the first body to rotate from the open position to the close position relative to the second body, the contact portion contacts the hinge to increase the friction of the pivot part relative to the hinge.

4. The hinge mechanism of claim 1 , wherein the friction part has a fixing portion and the fixing portion is assembled together with the pivot part.

5. The hinge mechanism of claim 1 , wherein the pivot part includes a first pivot portion and a second pivot portion moved with the first pivot portion, the first pivot portion being suitable to be connected to the second body, and the friction part being located between the first pivot portion and the second pivot portion.

6. The hinge mechanism of claim 1 , further comprising:

a locking portion locked to the hinge.

7. The hinge mechanism of claim 6 , further comprising:

a linking-up part telescoped on the hinge and located between the locking portion and the friction part, and the linking-up part being locked tightly to the hinge through the locking portion.

8. The hinge mechanism of claim 1 , further comprising:

a holder suitable to be fixed on the first body, wherein the hinge is fixed on the holder.