Notebook computer having a rotatable display module

A pivot device for rotating a second housing in a sunken part, wherein the sunken part includes an inner front wall and an inner side wall, wherein the second housing includes a front panel and a side panel, wherein the pivot device comprises:

• an elastic device for returning the second housing rotate from a second position to a first position;
• a protrusion slidably disposed on the side panel;
• and
• a guide track disposed on the inner side wall, wherein the guide track includes a first fixer and a second fixer, and wherein when the second housing is rotated, the protrusion moves between the first fixer and the second fixer along the guide track;
• wherein when the protrusion is coupled to the first fixer, the second housing is located in the first position, and the front panel faces a first direction, and wherein when the protrusion is coupled to the second fixer, the second housing is located in the second position, and the front panel faces a second direction.

An electronic device comprising:

• a first housing having a sunken part, wherein the sunken part includes an inner front wall and an inner side wall;
• a second housing having a front panel and a side panel, rotatably disposed in the sunken part between a first position and a second position;
• an elastic device for returning the second housing from the second position to the first position;
• a protrusion slidably disposed on the inner side wall of the first housing;
• and
• a guide track disposed on the side panel of the second housing, wherein the guide track includes a first fixer and a second fixer, and wherein when the second housing is rotated, the protrusion moves between the first fixer and the second fixer along the guide track;
• wherein when the protrusion is coupled to the first fixer, the second housing is located in the first position, and wherein when the protrusion is coupled to the second fixer, the second housing is located in the second position.