Electronic device and pivotable assembly

1. An electronic device, comprising:

a casing, the casing comprising a host and a display, the display is pivotally disposed at the host and is rotatable around an axis of rotation relative to the host, wherein the host has a first side edge and a second side edge, the first side edge is located on one side of the host away from the axis of rotation, the second side edge is located between the first side edge and the axis of rotation;

only three antenna assemblies, each disposed at the host, consisting of:

a first antenna assembly;

a second antenna assembly; and

a third antenna assembly;

wherein the third antenna assembly is rotatably disposed in a recess formed on a top surface of the casing, the recess located between the axis of rotation and the first side edge, and the first antenna assembly and the second antenna assembly are fixed at the casing; and

wherein the first antenna assembly and the second antenna assembly are located on the first side edge, and the third antenna assembly is located on the second side edge.

2. The electronic device according to claim 1 , further comprising:

a pivotable assembly disposed in the recess, comprising:

an assembly member;

a rotating member, pivotally disposed at the assembly member, the rotating member being rotatable along an axis of rotation relative to the assembly member; and

an antenna mounting plate, disposed at the rotating member, the antenna mounting plate having a mounting surface back facing the rotating member, the mounting surface being;

wherein, the axis of rotation is parallel to a normal line of the mounting surface of the antenna mounting plate;

wherein, the third antenna assembly is mounted on the mounting surface.

3. The electronic device according to claim 2 , further comprising a heat dissipating member; wherein, the assembly member and the rotating member are of a heat conductive material, and the heat dissipating member is stacked on the rotating member and is disposed between the third antenna assembly and the rotating member.

4. The electronic device according to claim 2 , wherein the antenna mounting plate comprises a power connector, and the power connector is for electrically connecting to the third antenna assembly.

5. The electronic device according to claim 2 , further comprising a pivotable pivotal member; wherein, the assembly member has at least one first pivotal hole, the rotating member has a second pivotal hole, and the pivotal member passes through the second pivotal hole of the rotating member and the at least one first pivotal hole.

6. The electronic device according to claim 5 , wherein the at least one first pivotal hole comprises a plurality of first pivotal holes, the plurality of first pivotal holes are kept at different distances from one of sides of the assembly member, and the rotating member is rotatable by different axes of rotation relative to the assembly member by means of being selectively pivotally connected to different ones of the plurality of first pivotal holes.

7. The electronic device according to claim 5 , further comprising a fixing member; wherein, the rotating member is fixed at the assembly member by means of the fixing member.